diff --git a/package-lock.json b/package-lock.json
index 220ab44e..6354a181 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -10679,9 +10679,9 @@
       "dev": true
     },
     "mini-css-extract-plugin": {
-      "version": "0.9.0",
-      "resolved": "https://registry.npmjs.org/mini-css-extract-plugin/-/mini-css-extract-plugin-0.9.0.tgz",
-      "integrity": "sha512-lp3GeY7ygcgAmVIcRPBVhIkf8Us7FZjA+ILpal44qLdSu11wmjKQ3d9k15lfD7pO4esu9eUIAW7qiYIBppv40A==",
+      "version": "0.10.0",
+      "resolved": "https://registry.npmjs.org/mini-css-extract-plugin/-/mini-css-extract-plugin-0.10.0.tgz",
+      "integrity": "sha512-QgKgJBjaJhxVPwrLNqqwNS0AGkuQQ31Hp4xGXEK/P7wehEg6qmNtReHKai3zRXqY60wGVWLYcOMJK2b98aGc3A==",
       "dev": true,
       "requires": {
         "loader-utils": "^1.1.0",
diff --git a/package.json b/package.json
index e53236df..ad72e6a6 100644
--- a/package.json
+++ b/package.json
@@ -78,7 +78,7 @@
     "less-loader": "^6.2.0",
     "lint-staged": "^10.2.11",
     "memfs": "^3.2.0",
-    "mini-css-extract-plugin": "^0.9.0",
+    "mini-css-extract-plugin": "^0.10.0",
     "npm-run-all": "^4.1.5",
     "postcss-loader": "^3.0.0",
     "postcss-preset-env": "^6.7.0",
@@ -91,7 +91,7 @@
     "stylus": "^0.54.8",
     "stylus-loader": "^3.0.2",
     "url-loader": "^4.1.0",
-    "webpack": "^4.44.0"
+    "webpack": "^4.44.1"
   },
   "keywords": [
     "webpack",
diff --git a/src/utils.js b/src/utils.js
index e08a74cc..49f37d29 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -414,7 +414,7 @@ function normalizeSourceMapForRuntime(map, loaderContext) {
         path.relative(loaderContext.rootContext, absoluteSource)
       );
 
-      return `webpack:///${contextifyPath}`;
+      return `webpack://${contextifyPath}`;
     });
   }
 
diff --git a/test/__snapshots__/sourceMap-option.test.js.snap b/test/__snapshots__/sourceMap-option.test.js.snap
index f016508c..5b466646 100644
--- a/test/__snapshots__/sourceMap-option.test.js.snap
+++ b/test/__snapshots__/sourceMap-option.test.js.snap
@@ -1,8 +1,8 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`"sourceMap" option false should not generate source maps when source maps equal to "null" from an other loader: errors 1`] = `Array []`;
+exports[`"sourceMap" option false should not generate source maps when previous loader does not generate source maps: errors 1`] = `Array []`;
 
-exports[`"sourceMap" option false should not generate source maps when source maps equal to "null" from an other loader: module 1`] = `
+exports[`"sourceMap" option false should not generate source maps when previous loader does not generate source maps: module 1`] = `
 "// Imports
 import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
 import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.css\\";
@@ -15,7 +15,7 @@ export default ___CSS_LOADER_EXPORT___;
 "
 `;
 
-exports[`"sourceMap" option false should not generate source maps when source maps equal to "null" from an other loader: result 1`] = `
+exports[`"sourceMap" option false should not generate source maps when previous loader does not generate source maps: result 1`] = `
 Array [
   Array [
     "../../src/index.js?[ident]!./source-map/nested/nested.css",
@@ -36,11 +36,11 @@ Array [
 ]
 `;
 
-exports[`"sourceMap" option false should not generate source maps when source maps equal to "null" from an other loader: warnings 1`] = `Array []`;
+exports[`"sourceMap" option false should not generate source maps when previous loader does not generate source maps: warnings 1`] = `Array []`;
 
-exports[`"sourceMap" option false should not generate source maps when source maps equal to "undefined" from an other loader: errors 1`] = `Array []`;
+exports[`"sourceMap" option false should not generate source maps when previous loader generates source maps: errors 1`] = `Array []`;
 
-exports[`"sourceMap" option false should not generate source maps when source maps equal to "undefined" from an other loader: module 1`] = `
+exports[`"sourceMap" option false should not generate source maps when previous loader generates source maps: module 1`] = `
 "// Imports
 import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
 import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.css\\";
@@ -53,7 +53,7 @@ export default ___CSS_LOADER_EXPORT___;
 "
 `;
 
-exports[`"sourceMap" option false should not generate source maps when source maps equal to "undefined" from an other loader: result 1`] = `
+exports[`"sourceMap" option false should not generate source maps when previous loader generates source maps: result 1`] = `
 Array [
   Array [
     "../../src/index.js?[ident]!./source-map/nested/nested.css",
@@ -74,149 +74,7 @@ Array [
 ]
 `;
 
-exports[`"sourceMap" option false should not generate source maps when source maps equal to "undefined" from an other loader: warnings 1`] = `Array []`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid and string from an other loader: errors 1`] = `Array []`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid and string from an other loader: module 1`] = `
-"// Imports
-import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
-import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.css\\";
-var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(false);
-___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
-// Module
-___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\"]);
-// Exports
-export default ___CSS_LOADER_EXPORT___;
-"
-`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid and string from an other loader: result 1`] = `
-Array [
-  Array [
-    "../../src/index.js?[ident]!./source-map/nested/nested.css",
-    ".nested {
-  color: blue;
-}
-",
-    "",
-  ],
-  Array [
-    "./source-map/basic.css",
-    ".class {
-  color: red;
-}
-",
-    "",
-  ],
-]
-`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid and string from an other loader: warnings 1`] = `Array []`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid from an other loader (\`postcss-loader\`): errors 1`] = `Array []`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid from an other loader (\`postcss-loader\`): module 1`] = `
-"// Imports
-import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
-import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.postcss.css\\";
-var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(false);
-___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
-// Module
-___CSS_LOADER_EXPORT___.push([module.id, \\":root {\\\\n  --fontSize: 1rem;\\\\n  --mainColor: rgba(18,52,86,0.47059);\\\\n  --secondaryColor: rgba(102, 51, 153, 0.9);\\\\n}\\\\n\\\\nhtml {\\\\n  overflow-x: hidden;\\\\n  overflow-y: auto;\\\\n  overflow: hidden auto;\\\\n}\\\\n\\\\n@media (max-width: 50rem) {\\\\n  body {\\\\n    color: rgba(18,52,86,0.47059);\\\\n    color: var(--mainColor);\\\\n    font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, sans-serif;\\\\n    font-size: 1rem;\\\\n    font-size: var(--fontSize);\\\\n    line-height: calc(1rem * 1.5);\\\\n    line-height: calc(var(--fontSize) * 1.5);\\\\n    word-wrap: break-word;\\\\n    padding-left: calc(1rem / 2 + 1px);\\\\n    padding-right: calc(1rem / 2 + 1px);\\\\n    padding-left: calc(var(--fontSize) / 2 + 1px);\\\\n    padding-right: calc(var(--fontSize) / 2 + 1px);\\\\n  }\\\\n}\\\\n\\\\nh1,h2,h3,h4,h5,h6 {\\\\n  margin-top: 0;\\\\n  margin-bottom: 0;\\\\n}\\\\n\\\\na {\\\\n  color: rgba(0, 0, 255, 0.9)\\\\n}\\\\n\\\\na:hover {\\\\n   color: #639;\\\\n }\\\\n\\", \\"\\"]);
-// Exports
-export default ___CSS_LOADER_EXPORT___;
-"
-`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid from an other loader (\`postcss-loader\`): result 1`] = `
-Array [
-  Array [
-    "../../src/index.js?[ident]!./source-map/nested/nested.postcss.css",
-    ".nested {
-  color: blue;
-}
-",
-    "",
-  ],
-  Array [
-    "./source-map/basic.postcss.css",
-    ":root {
-  --fontSize: 1rem;
-  --mainColor: rgba(18,52,86,0.47059);
-  --secondaryColor: rgba(102, 51, 153, 0.9);
-}
-
-html {
-  overflow-x: hidden;
-  overflow-y: auto;
-  overflow: hidden auto;
-}
-
-@media (max-width: 50rem) {
-  body {
-    color: rgba(18,52,86,0.47059);
-    color: var(--mainColor);
-    font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, sans-serif;
-    font-size: 1rem;
-    font-size: var(--fontSize);
-    line-height: calc(1rem * 1.5);
-    line-height: calc(var(--fontSize) * 1.5);
-    word-wrap: break-word;
-    padding-left: calc(1rem / 2 + 1px);
-    padding-right: calc(1rem / 2 + 1px);
-    padding-left: calc(var(--fontSize) / 2 + 1px);
-    padding-right: calc(var(--fontSize) / 2 + 1px);
-  }
-}
-
-h1,h2,h3,h4,h5,h6 {
-  margin-top: 0;
-  margin-bottom: 0;
-}
-
-a {
-  color: rgba(0, 0, 255, 0.9)
-}
-
-a:hover {
-   color: #639;
- }
-",
-    "",
-  ],
-]
-`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid from an other loader (\`postcss-loader\`): warnings 1`] = `Array []`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid from an other loader (\`sass-loader\`): errors 1`] = `Array []`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid from an other loader (\`sass-loader\`): module 1`] = `
-"// Imports
-import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
-var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(false);
-// Module
-___CSS_LOADER_EXPORT___.push([module.id, \\"body {\\\\n  font: 100% Helvetica, sans-serif;\\\\n  color: #333;\\\\n}\\", \\"\\"]);
-// Exports
-export default ___CSS_LOADER_EXPORT___;
-"
-`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid from an other loader (\`sass-loader\`): result 1`] = `
-Array [
-  Array [
-    "./source-map/basic.scss",
-    "body {
-  font: 100% Helvetica, sans-serif;
-  color: #333;
-}",
-    "",
-  ],
-]
-`;
-
-exports[`"sourceMap" option false should not generate source maps when source maps is valid from an other loader (\`sass-loader\`): warnings 1`] = `Array []`;
+exports[`"sourceMap" option false should not generate source maps when previous loader generates source maps: warnings 1`] = `Array []`;
 
 exports[`"sourceMap" option false should not generate source maps: errors 1`] = `Array []`;
 
@@ -301,7 +159,7 @@ exports[`"sourceMap" option true should generate source maps #2: module 1`] = `
 import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
 var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
 // Module
-___CSS_LOADER_EXPORT___.push([module.id, \\".foo {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack:///source-map/with-query.css\\"],\\"names\\":[],\\"mappings\\":\\"AAAA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\".foo {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
+___CSS_LOADER_EXPORT___.push([module.id, \\".foo {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack://source-map/with-query.css\\"],\\"names\\":[],\\"mappings\\":\\"AAAA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\".foo {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
 // Exports
 export default ___CSS_LOADER_EXPORT___;
 "
@@ -320,7 +178,7 @@ Array [
       "mappings": "AAAA;EACE,UAAU;AACZ",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/with-query.css",
+        "webpack://source-map/with-query.css",
       ],
       "sourcesContent": Array [
         ".foo {
@@ -336,25 +194,25 @@ Array [
 
 exports[`"sourceMap" option true should generate source maps #2: warnings 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps equal to "null" from an other loader: errors 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps and do not change "[contenthash]" on different platform: errors 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps equal to "null" from an other loader: module 1`] = `
+exports[`"sourceMap" option true should generate source maps and do not change "[contenthash]" on different platform: module 1`] = `
 "// Imports
 import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
 import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.css\\";
 var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
 ___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
 // Module
-___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack:///source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
+___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack://test/fixtures/source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
 // Exports
 export default ___CSS_LOADER_EXPORT___;
 "
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps equal to "null" from an other loader: result 1`] = `
+exports[`"sourceMap" option true should generate source maps and do not change "[contenthash]" on different platform: result 1`] = `
 Array [
   Array [
-    "../../src/index.js?[ident]!./source-map/nested/nested.css",
+    "./src/index.js?[ident]!./test/fixtures/source-map/nested/nested.css",
     ".nested {
   color: blue;
 }
@@ -364,7 +222,7 @@ Array [
       "mappings": "AAAA;EACE,WAAW;AACb",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/nested/nested.css",
+        "webpack://test/fixtures/source-map/nested/nested.css",
       ],
       "sourcesContent": Array [
         ".nested {
@@ -376,7 +234,7 @@ Array [
     },
   ],
   Array [
-    "./source-map/basic.css",
+    "./test/fixtures/source-map/basic.css",
     ".class {
   color: red;
 }
@@ -386,7 +244,7 @@ Array [
       "mappings": "AAEA;EACE,UAAU;AACZ",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/basic.css",
+        "webpack://test/fixtures/source-map/basic.css",
       ],
       "sourcesContent": Array [
         "@import \\"./nested/nested.css\\";
@@ -402,160 +260,110 @@ Array [
 ]
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps equal to "null" from an other loader: warnings 1`] = `Array []`;
-
-exports[`"sourceMap" option true should generate source maps when source maps equal to "undefined" from an other loader: errors 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps and do not change "[contenthash]" on different platform: warnings 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps equal to "undefined" from an other loader: module 1`] = `
-"// Imports
-import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
-import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.css\\";
-var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
-___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
-// Module
-___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack:///source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
-// Exports
-export default ___CSS_LOADER_EXPORT___;
-"
-`;
+exports[`"sourceMap" option true should generate source maps when css was extracted and do not change "[contenthash]" on different platform: errors 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps equal to "undefined" from an other loader: result 1`] = `
-Array [
-  Array [
-    "../../src/index.js?[ident]!./source-map/nested/nested.css",
-    ".nested {
+exports[`"sourceMap" option true should generate source maps when css was extracted and do not change "[contenthash]" on different platform: extracted css 1`] = `
+".nested {
   color: blue;
 }
-",
-    "",
-    Object {
-      "mappings": "AAAA;EACE,WAAW;AACb",
-      "names": Array [],
-      "sources": Array [
-        "webpack:///source-map/nested/nested.css",
-      ],
-      "sourcesContent": Array [
-        ".nested {
-  color: blue;
+
+.class {
+  color: red;
 }
-",
-      ],
-      "version": 3,
-    },
+
+
+/*# sourceMappingURL=main.xxxxxxxxxxxxxxxxxxxx.css.map*/"
+`;
+
+exports[`"sourceMap" option true should generate source maps when css was extracted and do not change "[contenthash]" on different platform: source map 1`] = `
+Object {
+  "file": "main.xxxxxxxxxxxxxxxxxxxx.css",
+  "mappings": "AAAA;EACE,WAAW;AACb;;ACAA;EACE,UAAU;AACZ",
+  "names": Array [],
+  "sourceRoot": "",
+  "sources": Array [
+    "webpack:///test/fixtures/source-map/nested/nested.css",
+    "webpack:///test/fixtures/source-map/basic.css",
   ],
-  Array [
-    "./source-map/basic.css",
-    ".class {
-  color: red;
+  "sourcesContent": Array [
+    ".nested {
+  color: blue;
 }
 ",
-    "",
-    Object {
-      "mappings": "AAEA;EACE,UAAU;AACZ",
-      "names": Array [],
-      "sources": Array [
-        "webpack:///source-map/basic.css",
-      ],
-      "sourcesContent": Array [
-        "@import \\"./nested/nested.css\\";
+    "@import \\"./nested/nested.css\\";
 
 .class {
   color: red;
 }
 ",
-      ],
-      "version": 3,
-    },
   ],
-]
+  "version": 3,
+}
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps equal to "undefined" from an other loader: warnings 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when css was extracted and do not change "[contenthash]" on different platform: warnings 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid and is set sourceRoot: errors 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when css was extracted: errors 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid and is set sourceRoot: module 1`] = `
-"// Imports
-import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
-import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.css\\";
-var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
-___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
-// Module
-___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack:///source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
-// Exports
-export default ___CSS_LOADER_EXPORT___;
-"
-`;
-
-exports[`"sourceMap" option true should generate source maps when source maps is valid and is set sourceRoot: result 1`] = `
-Array [
-  Array [
-    "../../src/index.js?[ident]!./source-map/nested/nested.css",
-    ".nested {
+exports[`"sourceMap" option true should generate source maps when css was extracted: extracted css 1`] = `
+".nested {
   color: blue;
 }
-",
-    "",
-    Object {
-      "mappings": "AAAA;EACE,WAAW;AACb",
-      "names": Array [],
-      "sources": Array [
-        "webpack:///source-map/nested/nested.css",
-      ],
-      "sourcesContent": Array [
-        ".nested {
-  color: blue;
+
+.class {
+  color: red;
 }
-",
-      ],
-      "version": 3,
-    },
+
+
+/*# sourceMappingURL=main.css.map*/"
+`;
+
+exports[`"sourceMap" option true should generate source maps when css was extracted: source map 1`] = `
+Object {
+  "file": "main.css",
+  "mappings": "AAAA;EACE,WAAW;AACb;;ACAA;EACE,UAAU;AACZ",
+  "names": Array [],
+  "sourceRoot": "",
+  "sources": Array [
+    "webpack:///source-map/nested/nested.css",
+    "webpack:///source-map/basic.css",
   ],
-  Array [
-    "./source-map/basic.css",
-    ".class {
-  color: red;
+  "sourcesContent": Array [
+    ".nested {
+  color: blue;
 }
 ",
-    "",
-    Object {
-      "mappings": "AAEA;EACE,UAAU;AACZ",
-      "names": Array [],
-      "sources": Array [
-        "webpack:///source-map/basic.css",
-      ],
-      "sourcesContent": Array [
-        "@import \\"./nested/nested.css\\";
+    "@import \\"./nested/nested.css\\";
 
 .class {
   color: red;
 }
 ",
-      ],
-      "version": 3,
-    },
   ],
-]
+  "version": 3,
+}
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid and is set sourceRoot: warnings 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when css was extracted: warnings 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid and string from an other loader: errors 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when previous loader does not generate source maps: errors 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid and string from an other loader: module 1`] = `
+exports[`"sourceMap" option true should generate source maps when previous loader does not generate source maps: module 1`] = `
 "// Imports
 import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
 import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.css\\";
 var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
 ___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
 // Module
-___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack:///source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
+___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack://source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
 // Exports
 export default ___CSS_LOADER_EXPORT___;
 "
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid and string from an other loader: result 1`] = `
+exports[`"sourceMap" option true should generate source maps when previous loader does not generate source maps: result 1`] = `
 Array [
   Array [
     "../../src/index.js?[ident]!./source-map/nested/nested.css",
@@ -568,7 +376,7 @@ Array [
       "mappings": "AAAA;EACE,WAAW;AACb",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/nested/nested.css",
+        "webpack://source-map/nested/nested.css",
       ],
       "sourcesContent": Array [
         ".nested {
@@ -590,7 +398,7 @@ Array [
       "mappings": "AAEA;EACE,UAAU;AACZ",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/basic.css",
+        "webpack://source-map/basic.css",
       ],
       "sourcesContent": Array [
         "@import \\"./nested/nested.css\\";
@@ -606,22 +414,22 @@ Array [
 ]
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid and string from an other loader: warnings 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when previous loader does not generate source maps: warnings 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`less-loader\`): errors 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("less-loader"): errors 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`less-loader\`): module 1`] = `
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("less-loader"): module 1`] = `
 "// Imports
 import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
 var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
 // Module
-___CSS_LOADER_EXPORT___.push([module.id, \\"body {\\\\n  font: 100% Helvetica, sans-serif;\\\\n  color: #333;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack:///source-map/base.less\\"],\\"names\\":[],\\"mappings\\":\\"AAGA;EACE,gCAAA;EACA,WAAA;AAFF\\",\\"sourcesContent\\":[\\"@font-stack:    Helvetica, sans-serif;\\\\n@primary-color: #333;\\\\n\\\\nbody {\\\\n  font: 100% @font-stack;\\\\n  color: @primary-color;\\\\n}\\\\n\\"]}]);
+___CSS_LOADER_EXPORT___.push([module.id, \\"body {\\\\n  font: 100% Helvetica, sans-serif;\\\\n  color: #333;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack://source-map/base.less\\"],\\"names\\":[],\\"mappings\\":\\"AAGA;EACE,gCAAA;EACA,WAAA;AAFF\\",\\"sourcesContent\\":[\\"@font-stack:    Helvetica, sans-serif;\\\\n@primary-color: #333;\\\\n\\\\nbody {\\\\n  font: 100% @font-stack;\\\\n  color: @primary-color;\\\\n}\\\\n\\"]}]);
 // Exports
 export default ___CSS_LOADER_EXPORT___;
 "
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`less-loader\`): result 1`] = `
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("less-loader"): result 1`] = `
 Array [
   Array [
     "./source-map/base.less",
@@ -635,7 +443,7 @@ Array [
       "mappings": "AAGA;EACE,gCAAA;EACA,WAAA;AAFF",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/base.less",
+        "webpack://source-map/base.less",
       ],
       "sourcesContent": Array [
         "@font-stack:    Helvetica, sans-serif;
@@ -653,24 +461,24 @@ body {
 ]
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`less-loader\`): warnings 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("less-loader"): warnings 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`postcss-loader\`): errors 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("postcss-loader"): errors 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`postcss-loader\`): module 1`] = `
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("postcss-loader"): module 1`] = `
 "// Imports
 import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
 import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.postcss.css\\";
 var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
 ___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
 // Module
-___CSS_LOADER_EXPORT___.push([module.id, \\":root {\\\\n  --fontSize: 1rem;\\\\n  --mainColor: rgba(18,52,86,0.47059);\\\\n  --secondaryColor: rgba(102, 51, 153, 0.9);\\\\n}\\\\n\\\\nhtml {\\\\n  overflow-x: hidden;\\\\n  overflow-y: auto;\\\\n  overflow: hidden auto;\\\\n}\\\\n\\\\n@media (max-width: 50rem) {\\\\n  body {\\\\n    color: rgba(18,52,86,0.47059);\\\\n    color: var(--mainColor);\\\\n    font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, sans-serif;\\\\n    font-size: 1rem;\\\\n    font-size: var(--fontSize);\\\\n    line-height: calc(1rem * 1.5);\\\\n    line-height: calc(var(--fontSize) * 1.5);\\\\n    word-wrap: break-word;\\\\n    padding-left: calc(1rem / 2 + 1px);\\\\n    padding-right: calc(1rem / 2 + 1px);\\\\n    padding-left: calc(var(--fontSize) / 2 + 1px);\\\\n    padding-right: calc(var(--fontSize) / 2 + 1px);\\\\n  }\\\\n}\\\\n\\\\nh1,h2,h3,h4,h5,h6 {\\\\n  margin-top: 0;\\\\n  margin-bottom: 0;\\\\n}\\\\n\\\\na {\\\\n  color: rgba(0, 0, 255, 0.9)\\\\n}\\\\n\\\\na:hover {\\\\n   color: #639;\\\\n }\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack:///source-map/basic.postcss.css\\"],\\"names\\":[],\\"mappings\\":\\"AAKA;EACE,gBAAgB;EAChB,mCAAsB;EACtB,yCAA4C;AAC9C;;AAEA;EACE,kBAAqB;EAArB,gBAAqB;EAArB,qBAAqB;AACvB;;AAEA;EACE;IACE,6BAAuB;IAAvB,uBAAuB;IACvB,iGAAsB;IACtB,eAA0B;IAA1B,0BAA0B;IAC1B,6BAAwC;IAAxC,wCAAwC;IACxC,qBAAyB;IACzB,kCAA+C;IAA/C,mCAA+C;IAA/C,6CAA+C;IAA/C,8CAA+C;EACjD;AACF;;AAEA;EACE,aAAe;EAAf,gBAAe;AACjB;;AAEA;EACE;AAKF;;AAHA;GACG,WAAoB;CACtB\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.postcss.css\\\\\\";\\\\n\\\\n@custom-media --viewport-medium (width <= 50rem);\\\\n@custom-selector :--heading h1, h2, h3, h4, h5, h6;\\\\n\\\\n:root {\\\\n  --fontSize: 1rem;\\\\n  --mainColor: #12345678;\\\\n  --secondaryColor: lab(32.5 38.5 -47.6 / 90%);\\\\n}\\\\n\\\\nhtml {\\\\n  overflow: hidden auto;\\\\n}\\\\n\\\\n@media (--viewport-medium) {\\\\n  body {\\\\n    color: var(--mainColor);\\\\n    font-family: system-ui;\\\\n    font-size: var(--fontSize);\\\\n    line-height: calc(var(--fontSize) * 1.5);\\\\n    overflow-wrap: break-word;\\\\n    padding-inline: calc(var(--fontSize) / 2 + 1px);\\\\n  }\\\\n}\\\\n\\\\n:--heading {\\\\n  margin-block: 0;\\\\n}\\\\n\\\\na {\\\\n  color: rgb(0 0 100% / 90%);\\\\n\\\\n&:hover {\\\\n   color: rebeccapurple;\\\\n }\\\\n}\\\\n\\"]}]);
+___CSS_LOADER_EXPORT___.push([module.id, \\":root {\\\\n  --fontSize: 1rem;\\\\n  --mainColor: rgba(18,52,86,0.47059);\\\\n  --secondaryColor: rgba(102, 51, 153, 0.9);\\\\n}\\\\n\\\\nhtml {\\\\n  overflow-x: hidden;\\\\n  overflow-y: auto;\\\\n  overflow: hidden auto;\\\\n}\\\\n\\\\n@media (max-width: 50rem) {\\\\n  body {\\\\n    color: rgba(18,52,86,0.47059);\\\\n    color: var(--mainColor);\\\\n    font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, sans-serif;\\\\n    font-size: 1rem;\\\\n    font-size: var(--fontSize);\\\\n    line-height: calc(1rem * 1.5);\\\\n    line-height: calc(var(--fontSize) * 1.5);\\\\n    word-wrap: break-word;\\\\n    padding-left: calc(1rem / 2 + 1px);\\\\n    padding-right: calc(1rem / 2 + 1px);\\\\n    padding-left: calc(var(--fontSize) / 2 + 1px);\\\\n    padding-right: calc(var(--fontSize) / 2 + 1px);\\\\n  }\\\\n}\\\\n\\\\nh1,h2,h3,h4,h5,h6 {\\\\n  margin-top: 0;\\\\n  margin-bottom: 0;\\\\n}\\\\n\\\\na {\\\\n  color: rgba(0, 0, 255, 0.9)\\\\n}\\\\n\\\\na:hover {\\\\n   color: #639;\\\\n }\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack://source-map/basic.postcss.css\\"],\\"names\\":[],\\"mappings\\":\\"AAKA;EACE,gBAAgB;EAChB,mCAAsB;EACtB,yCAA4C;AAC9C;;AAEA;EACE,kBAAqB;EAArB,gBAAqB;EAArB,qBAAqB;AACvB;;AAEA;EACE;IACE,6BAAuB;IAAvB,uBAAuB;IACvB,iGAAsB;IACtB,eAA0B;IAA1B,0BAA0B;IAC1B,6BAAwC;IAAxC,wCAAwC;IACxC,qBAAyB;IACzB,kCAA+C;IAA/C,mCAA+C;IAA/C,6CAA+C;IAA/C,8CAA+C;EACjD;AACF;;AAEA;EACE,aAAe;EAAf,gBAAe;AACjB;;AAEA;EACE;AAKF;;AAHA;GACG,WAAoB;CACtB\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.postcss.css\\\\\\";\\\\n\\\\n@custom-media --viewport-medium (width <= 50rem);\\\\n@custom-selector :--heading h1, h2, h3, h4, h5, h6;\\\\n\\\\n:root {\\\\n  --fontSize: 1rem;\\\\n  --mainColor: #12345678;\\\\n  --secondaryColor: lab(32.5 38.5 -47.6 / 90%);\\\\n}\\\\n\\\\nhtml {\\\\n  overflow: hidden auto;\\\\n}\\\\n\\\\n@media (--viewport-medium) {\\\\n  body {\\\\n    color: var(--mainColor);\\\\n    font-family: system-ui;\\\\n    font-size: var(--fontSize);\\\\n    line-height: calc(var(--fontSize) * 1.5);\\\\n    overflow-wrap: break-word;\\\\n    padding-inline: calc(var(--fontSize) / 2 + 1px);\\\\n  }\\\\n}\\\\n\\\\n:--heading {\\\\n  margin-block: 0;\\\\n}\\\\n\\\\na {\\\\n  color: rgb(0 0 100% / 90%);\\\\n\\\\n&:hover {\\\\n   color: rebeccapurple;\\\\n }\\\\n}\\\\n\\"]}]);
 // Exports
 export default ___CSS_LOADER_EXPORT___;
 "
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`postcss-loader\`): result 1`] = `
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("postcss-loader"): result 1`] = `
 Array [
   Array [
     "../../src/index.js?[ident]!./source-map/nested/nested.postcss.css",
@@ -683,7 +491,7 @@ Array [
       "mappings": "AAAA;EACE,WAAW;AACb",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/nested/nested.postcss.css",
+        "webpack://source-map/nested/nested.postcss.css",
       ],
       "sourcesContent": Array [
         ".nested {
@@ -743,7 +551,7 @@ a:hover {
       "mappings": "AAKA;EACE,gBAAgB;EAChB,mCAAsB;EACtB,yCAA4C;AAC9C;;AAEA;EACE,kBAAqB;EAArB,gBAAqB;EAArB,qBAAqB;AACvB;;AAEA;EACE;IACE,6BAAuB;IAAvB,uBAAuB;IACvB,iGAAsB;IACtB,eAA0B;IAA1B,0BAA0B;IAC1B,6BAAwC;IAAxC,wCAAwC;IACxC,qBAAyB;IACzB,kCAA+C;IAA/C,mCAA+C;IAA/C,6CAA+C;IAA/C,8CAA+C;EACjD;AACF;;AAEA;EACE,aAAe;EAAf,gBAAe;AACjB;;AAEA;EACE;AAKF;;AAHA;GACG,WAAoB;CACtB",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/basic.postcss.css",
+        "webpack://source-map/basic.postcss.css",
       ],
       "sourcesContent": Array [
         "@import \\"./nested/nested.postcss.css\\";
@@ -791,22 +599,22 @@ a {
 ]
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`postcss-loader\`): warnings 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("postcss-loader"): warnings 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`stylus-loader\`): errors 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("stylus-loader"): errors 1`] = `Array []`;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`stylus-loader\`): module 1`] = `
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("stylus-loader"): module 1`] = `
 "// Imports
 import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
 var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
 // Module
-___CSS_LOADER_EXPORT___.push([module.id, \\"body {\\\\n  font: 14px/1.5 Helvetica, arial, sans-serif;\\\\n}\\\\nbody #logo {\\\\n  border-radius: 5px;\\\\n}\\\\n/*# sourceMappingURL=test/fixtures/source-map/base.css.map */\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack:///source-map/base.styl\\"],\\"names\\":[],\\"mappings\\":\\"AAAA;EACE,2CAAwB;AAC1B;AAAE;EACE,kBAAe;AAEnB;AACA,4DAA4D\\",\\"sourcesContent\\":[\\"body {\\\\n  font: 14px/1.5 Helvetica, arial, sans-serif;\\\\n  #logo {\\\\n    border-radius: 5px;\\\\n  }\\\\n}\\\\n\\"]}]);
+___CSS_LOADER_EXPORT___.push([module.id, \\"body {\\\\n  font: 14px/1.5 Helvetica, arial, sans-serif;\\\\n}\\\\nbody #logo {\\\\n  border-radius: 5px;\\\\n}\\\\n/*# sourceMappingURL=test/fixtures/source-map/base.css.map */\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack://source-map/base.styl\\"],\\"names\\":[],\\"mappings\\":\\"AAAA;EACE,2CAAwB;AAC1B;AAAE;EACE,kBAAe;AAEnB;AACA,4DAA4D\\",\\"sourcesContent\\":[\\"body {\\\\n  font: 14px/1.5 Helvetica, arial, sans-serif;\\\\n  #logo {\\\\n    border-radius: 5px;\\\\n  }\\\\n}\\\\n\\"]}]);
 // Exports
 export default ___CSS_LOADER_EXPORT___;
 "
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`stylus-loader\`): result 1`] = `
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("stylus-loader"): result 1`] = `
 Array [
   Array [
     "./source-map/base.styl",
@@ -822,7 +630,7 @@ body #logo {
       "mappings": "AAAA;EACE,2CAAwB;AAC1B;AAAE;EACE,kBAAe;AAEnB;AACA,4DAA4D",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/base.styl",
+        "webpack://source-map/base.styl",
       ],
       "sourcesContent": Array [
         "body {
@@ -839,7 +647,143 @@ body #logo {
 ]
 `;
 
-exports[`"sourceMap" option true should generate source maps when source maps is valid from an other loader (\`stylus-loader\`): warnings 1`] = `Array []`;
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps ("stylus-loader"): warnings 1`] = `Array []`;
+
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps with "sourceRoot": errors 1`] = `Array []`;
+
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps with "sourceRoot": module 1`] = `
+"// Imports
+import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
+import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.css\\";
+var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
+___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
+// Module
+___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack://source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
+// Exports
+export default ___CSS_LOADER_EXPORT___;
+"
+`;
+
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps with "sourceRoot": result 1`] = `
+Array [
+  Array [
+    "../../src/index.js?[ident]!./source-map/nested/nested.css",
+    ".nested {
+  color: blue;
+}
+",
+    "",
+    Object {
+      "mappings": "AAAA;EACE,WAAW;AACb",
+      "names": Array [],
+      "sources": Array [
+        "webpack://source-map/nested/nested.css",
+      ],
+      "sourcesContent": Array [
+        ".nested {
+  color: blue;
+}
+",
+      ],
+      "version": 3,
+    },
+  ],
+  Array [
+    "./source-map/basic.css",
+    ".class {
+  color: red;
+}
+",
+    "",
+    Object {
+      "mappings": "AAEA;EACE,UAAU;AACZ",
+      "names": Array [],
+      "sources": Array [
+        "webpack://source-map/basic.css",
+      ],
+      "sourcesContent": Array [
+        "@import \\"./nested/nested.css\\";
+
+.class {
+  color: red;
+}
+",
+      ],
+      "version": 3,
+    },
+  ],
+]
+`;
+
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps with "sourceRoot": warnings 1`] = `Array []`;
+
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps without "sourceRoot": errors 1`] = `Array []`;
+
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps without "sourceRoot": module 1`] = `
+"// Imports
+import ___CSS_LOADER_API_IMPORT___ from \\"../../../src/runtime/api.js\\";
+import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident]!./nested/nested.css\\";
+var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
+___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
+// Module
+___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack://source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
+// Exports
+export default ___CSS_LOADER_EXPORT___;
+"
+`;
+
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps without "sourceRoot": result 1`] = `
+Array [
+  Array [
+    "../../src/index.js?[ident]!./source-map/nested/nested.css",
+    ".nested {
+  color: blue;
+}
+",
+    "",
+    Object {
+      "mappings": "AAAA;EACE,WAAW;AACb",
+      "names": Array [],
+      "sources": Array [
+        "webpack://source-map/nested/nested.css",
+      ],
+      "sourcesContent": Array [
+        ".nested {
+  color: blue;
+}
+",
+      ],
+      "version": 3,
+    },
+  ],
+  Array [
+    "./source-map/basic.css",
+    ".class {
+  color: red;
+}
+",
+    "",
+    Object {
+      "mappings": "AAEA;EACE,UAAU;AACZ",
+      "names": Array [],
+      "sources": Array [
+        "webpack://source-map/basic.css",
+      ],
+      "sourcesContent": Array [
+        "@import \\"./nested/nested.css\\";
+
+.class {
+  color: red;
+}
+",
+      ],
+      "version": 3,
+    },
+  ],
+]
+`;
+
+exports[`"sourceMap" option true should generate source maps when previous loader generates source maps without "sourceRoot": warnings 1`] = `Array []`;
 
 exports[`"sourceMap" option true should generate source maps: errors 1`] = `Array []`;
 
@@ -850,7 +794,7 @@ import ___CSS_LOADER_AT_RULE_IMPORT_0___ from \\"-!../../../src/index.js??[ident
 var ___CSS_LOADER_EXPORT___ = ___CSS_LOADER_API_IMPORT___(true);
 ___CSS_LOADER_EXPORT___.i(___CSS_LOADER_AT_RULE_IMPORT_0___);
 // Module
-___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack:///source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
+___CSS_LOADER_EXPORT___.push([module.id, \\".class {\\\\n  color: red;\\\\n}\\\\n\\", \\"\\",{\\"version\\":3,\\"sources\\":[\\"webpack://source-map/basic.css\\"],\\"names\\":[],\\"mappings\\":\\"AAEA;EACE,UAAU;AACZ\\",\\"sourcesContent\\":[\\"@import \\\\\\"./nested/nested.css\\\\\\";\\\\n\\\\n.class {\\\\n  color: red;\\\\n}\\\\n\\"]}]);
 // Exports
 export default ___CSS_LOADER_EXPORT___;
 "
@@ -869,7 +813,7 @@ Array [
       "mappings": "AAAA;EACE,WAAW;AACb",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/nested/nested.css",
+        "webpack://source-map/nested/nested.css",
       ],
       "sourcesContent": Array [
         ".nested {
@@ -891,7 +835,7 @@ Array [
       "mappings": "AAEA;EACE,UAAU;AACZ",
       "names": Array [],
       "sources": Array [
-        "webpack:///source-map/basic.css",
+        "webpack://source-map/basic.css",
       ],
       "sourcesContent": Array [
         "@import \\"./nested/nested.css\\";
diff --git a/test/helpers/execute.js b/test/helpers/execute.js
index 866001ae..8ae07d81 100644
--- a/test/helpers/execute.js
+++ b/test/helpers/execute.js
@@ -14,7 +14,7 @@ export default (code) => {
 
   // eslint-disable-next-line no-underscore-dangle
   module._compile(
-    `let __export__;${code};module.exports = __export__;`,
+    `let __export__;${code};\nmodule.exports = __export__;`,
     resource
   );
 
diff --git a/test/sourceMap-option.test.js b/test/sourceMap-option.test.js
index 7e486685..d4845340 100644
--- a/test/sourceMap-option.test.js
+++ b/test/sourceMap-option.test.js
@@ -1,6 +1,8 @@
 import path from 'path';
 
+import webpack from 'webpack';
 import postcssPresetEnv from 'postcss-preset-env';
+import MiniCssExtractPlugin from 'mini-css-extract-plugin';
 
 import {
   compile,
@@ -9,6 +11,7 @@ import {
   getExecutedCode,
   getModuleSource,
   getWarnings,
+  readAsset,
 } from './helpers/index';
 
 jest.setTimeout(10000);
@@ -63,7 +66,7 @@ describe('"sourceMap" option', () => {
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should generate source maps when source maps equal to "null" from an other loader', async () => {
+    it('should generate source maps when previous loader does not generate source maps', async () => {
       const compiler = getCompiler(
         './source-map/basic.js',
         {},
@@ -104,49 +107,7 @@ describe('"sourceMap" option', () => {
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should generate source maps when source maps equal to "undefined" from an other loader', async () => {
-      const compiler = getCompiler(
-        './source-map/basic.js',
-        {},
-        {
-          module: {
-            rules: [
-              {
-                test: /\.css$/i,
-                use: [
-                  {
-                    loader: path.resolve(__dirname, '../src'),
-                    options: { sourceMap: true },
-                  },
-                  {
-                    loader: path.resolve(
-                      __dirname,
-                      './fixtures/source-map-loader.js'
-                    ),
-                    options: {
-                      // eslint-disable-next-line no-undefined
-                      sourceMap: undefined,
-                    },
-                  },
-                ],
-              },
-            ],
-          },
-        }
-      );
-      const stats = await compile(compiler);
-
-      expect(getModuleSource('./source-map/basic.css', stats)).toMatchSnapshot(
-        'module'
-      );
-      expect(
-        getExecutedCode('main.bundle.js', compiler, stats)
-      ).toMatchSnapshot('result');
-      expect(getWarnings(stats)).toMatchSnapshot('warnings');
-      expect(getErrors(stats)).toMatchSnapshot('errors');
-    });
-
-    it('should generate source maps when source maps is valid and string from an other loader', async () => {
+    it('should generate source maps when previous loader generates source maps without "sourceRoot"', async () => {
       const absolutePath = path.resolve(
         __dirname,
         'fixtures',
@@ -203,7 +164,7 @@ describe('"sourceMap" option', () => {
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should generate source maps when source maps is valid and is set sourceRoot', async () => {
+    it('should generate source maps when previous loader generates source maps with "sourceRoot"', async () => {
       const absoluteSourceRoot = path.resolve(
         __dirname,
         'fixtures',
@@ -260,7 +221,7 @@ describe('"sourceMap" option', () => {
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should generate source maps when source maps is valid from an other loader (`postcss-loader`)', async () => {
+    it('should generate source maps when previous loader generates source maps ("postcss-loader")', async () => {
       const compiler = getCompiler(
         './source-map/basic-postcss.js',
         {},
@@ -301,7 +262,7 @@ describe('"sourceMap" option', () => {
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it.skip('should generate source maps when source maps is valid from an other loader (`sass-loader`)', async () => {
+    it.skip('should generate source maps when previous loader generates source maps ("sass-loader")', async () => {
       const compiler = getCompiler(
         './source-map/basic-scss.js',
         {},
@@ -343,7 +304,7 @@ describe('"sourceMap" option', () => {
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should generate source maps when source maps is valid from an other loader (`less-loader`)', async () => {
+    it('should generate source maps when previous loader generates source maps ("less-loader")', async () => {
       const compiler = getCompiler(
         './source-map/basic-less.js',
         {},
@@ -383,7 +344,7 @@ describe('"sourceMap" option', () => {
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should generate source maps when source maps is valid from an other loader (`stylus-loader`)', async () => {
+    it('should generate source maps when previous loader generates source maps ("stylus-loader")', async () => {
       const compiler = getCompiler(
         './source-map/basic-styl.js',
         {},
@@ -422,47 +383,31 @@ describe('"sourceMap" option', () => {
       expect(getWarnings(stats)).toMatchSnapshot('warnings');
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
-  });
-
-  describe('false', () => {
-    it('should not generate source maps', async () => {
-      const compiler = getCompiler('./source-map/basic.js', {
-        sourceMap: false,
-      });
-      const stats = await compile(compiler);
-
-      expect(getModuleSource('./source-map/basic.css', stats)).toMatchSnapshot(
-        'module'
-      );
-      expect(
-        getExecutedCode('main.bundle.js', compiler, stats)
-      ).toMatchSnapshot('result');
-      expect(getWarnings(stats)).toMatchSnapshot('warnings');
-      expect(getErrors(stats)).toMatchSnapshot('errors');
-    });
 
-    it('should not generate source maps when source maps equal to "null" from an other loader', async () => {
+    it('should generate source maps and do not change "[contenthash]" on different platform', async () => {
       const compiler = getCompiler(
         './source-map/basic.js',
         {},
         {
+          devtool: 'source-map',
+          // webpack@4 has bug
+          // It uses readableIdentifier to generate the sources, which uses the RequestShortener,
+          // which has some problems with paths that are 2 folders above the context
+          context: path.resolve(__dirname, '..'),
+          output: {
+            path: path.resolve(__dirname, './outputs'),
+            filename: '[name].[contenthash].bundle.js',
+            chunkFilename: '[name].[contenthash].chunk.js',
+            publicPath: '/webpack/public/path/',
+          },
           module: {
             rules: [
               {
                 test: /\.css$/i,
-                use: [
+                rules: [
                   {
                     loader: path.resolve(__dirname, '../src'),
-                    options: { sourceMap: false },
-                  },
-                  {
-                    loader: path.resolve(
-                      __dirname,
-                      './fixtures/source-map-loader.js'
-                    ),
-                    options: {
-                      sourceMap: null,
-                    },
+                    options: { sourceMap: true },
                   },
                 ],
               },
@@ -471,40 +416,53 @@ describe('"sourceMap" option', () => {
         }
       );
       const stats = await compile(compiler);
-
-      expect(getModuleSource('./source-map/basic.css', stats)).toMatchSnapshot(
-        'module'
+      const chunkName = Object.keys(
+        stats.compilation.assets
+      ).find((assetName) => /\.js$/.test(assetName));
+
+      expect(chunkName).toBe(
+        webpack.version[0] === '5'
+          ? 'main.b58b73eca7517a2128fd.bundle.js'
+          : 'main.1e45307f085c8aadaf4c.bundle.js'
       );
       expect(
-        getExecutedCode('main.bundle.js', compiler, stats)
-      ).toMatchSnapshot('result');
+        getModuleSource('fixtures/source-map/basic.css', stats)
+      ).toMatchSnapshot('module');
+      expect(getExecutedCode(chunkName, compiler, stats)).toMatchSnapshot(
+        'result'
+      );
       expect(getWarnings(stats)).toMatchSnapshot('warnings');
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should not generate source maps when source maps equal to "undefined" from an other loader', async () => {
+    it('should generate source maps when css was extracted', async () => {
       const compiler = getCompiler(
         './source-map/basic.js',
         {},
         {
+          devtool: 'source-map',
+          output: {
+            path: path.resolve(__dirname, '../outputs'),
+            filename: '[name].bundle.js',
+            chunkFilename: '[name].chunk.js',
+            publicPath: '/webpack/public/path/',
+          },
+          plugins: [
+            new MiniCssExtractPlugin({
+              filename: '[name].css',
+            }),
+          ],
           module: {
             rules: [
               {
                 test: /\.css$/i,
-                use: [
+                rules: [
                   {
-                    loader: path.resolve(__dirname, '../src'),
-                    options: { sourceMap: false },
+                    loader: MiniCssExtractPlugin.loader,
                   },
                   {
-                    loader: path.resolve(
-                      __dirname,
-                      './fixtures/source-map-loader.js'
-                    ),
-                    options: {
-                      // eslint-disable-next-line no-undefined
-                      sourceMap: undefined,
-                    },
+                    loader: path.resolve(__dirname, '../src'),
+                    options: { sourceMap: true },
                   },
                 ],
               },
@@ -514,46 +472,48 @@ describe('"sourceMap" option', () => {
       );
       const stats = await compile(compiler);
 
-      expect(getModuleSource('./source-map/basic.css', stats)).toMatchSnapshot(
-        'module'
+      expect(readAsset('main.css', compiler, stats)).toMatchSnapshot(
+        'extracted css'
       );
       expect(
-        getExecutedCode('main.bundle.js', compiler, stats)
-      ).toMatchSnapshot('result');
+        JSON.parse(readAsset('main.css.map', compiler, stats))
+      ).toMatchSnapshot('source map');
       expect(getWarnings(stats)).toMatchSnapshot('warnings');
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should not generate source maps when source maps is valid and string from an other loader', async () => {
+    it('should generate source maps when css was extracted and do not change "[contenthash]" on different platform', async () => {
       const compiler = getCompiler(
         './source-map/basic.js',
         {},
         {
+          devtool: 'source-map',
+          // webpack@4 has bug
+          // It uses readableIdentifier to generate the sources, which uses the RequestShortener,
+          // which has some problems with paths that are 2 folders above the context
+          context: path.resolve(__dirname, '..'),
+          output: {
+            path: path.resolve(__dirname, '../outputs'),
+            filename: '[name].bundle.js',
+            chunkFilename: '[name].chunk.js',
+            publicPath: '/webpack/public/path/',
+          },
+          plugins: [
+            new MiniCssExtractPlugin({
+              filename: '[name].[contenthash].css',
+            }),
+          ],
           module: {
             rules: [
               {
                 test: /\.css$/i,
-                use: [
+                rules: [
                   {
-                    loader: path.resolve(__dirname, '../src'),
-                    options: { sourceMap: false },
+                    loader: MiniCssExtractPlugin.loader,
                   },
                   {
-                    loader: path.resolve(
-                      __dirname,
-                      './fixtures/source-map-loader.js'
-                    ),
-                    options: {
-                      sourceMap: JSON.stringify({
-                        foo: 'bar',
-                        version: 3,
-                        sources: ['basic.css'],
-                        names: [],
-                        mappings: 'AAAA;EACE,UAAU;AACZ',
-                        file: 'basic.css',
-                        sourcesContent: ['.class {\n  color: red;\n}\n'],
-                      }),
-                    },
+                    loader: path.resolve(__dirname, '../src'),
+                    options: { sourceMap: true },
                   },
                 ],
               },
@@ -562,6 +522,48 @@ describe('"sourceMap" option', () => {
         }
       );
       const stats = await compile(compiler);
+      const chunkName = Object.keys(
+        stats.compilation.assets
+      ).find((assetName) => /\.css$/.test(assetName));
+
+      const extractedCSS = readAsset(chunkName, compiler, stats);
+
+      expect(chunkName).toBe(
+        // TODO still buggy on webpack@4
+        webpack.version[0] === '5' ? 'main.8189c1c4f956dd69079a.css' : chunkName
+      );
+
+      expect(
+        extractedCSS.replace(
+          /=(.+?)\..+?\.css\.map/,
+          '=$1.xxxxxxxxxxxxxxxxxxxx.css.map'
+        )
+      ).toMatchSnapshot('extracted css');
+
+      const sourceMap = JSON.parse(
+        readAsset(`${chunkName}.map`, compiler, stats)
+      );
+
+      sourceMap.file = sourceMap.file.replace(
+        /^(.+?)\..+?\.css$/,
+        '$1.xxxxxxxxxxxxxxxxxxxx.css'
+      );
+      sourceMap.sources = sourceMap.sources.map((source) =>
+        source.replace('css-loader', '')
+      );
+
+      expect(sourceMap).toMatchSnapshot('source map');
+      expect(getWarnings(stats)).toMatchSnapshot('warnings');
+      expect(getErrors(stats)).toMatchSnapshot('errors');
+    });
+  });
+
+  describe('false', () => {
+    it('should not generate source maps', async () => {
+      const compiler = getCompiler('./source-map/basic.js', {
+        sourceMap: false,
+      });
+      const stats = await compile(compiler);
 
       expect(getModuleSource('./source-map/basic.css', stats)).toMatchSnapshot(
         'module'
@@ -573,9 +575,9 @@ describe('"sourceMap" option', () => {
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should not generate source maps when source maps is valid from an other loader (`postcss-loader`)', async () => {
+    it('should not generate source maps when previous loader does not generate source maps', async () => {
       const compiler = getCompiler(
-        './source-map/basic-postcss.js',
+        './source-map/basic.js',
         {},
         {
           module: {
@@ -585,14 +587,16 @@ describe('"sourceMap" option', () => {
                 use: [
                   {
                     loader: path.resolve(__dirname, '../src'),
-                    options: {
-                      sourceMap: false,
-                    },
+                    options: { sourceMap: false },
                   },
                   {
-                    loader: 'postcss-loader',
+                    loader: path.resolve(
+                      __dirname,
+                      './fixtures/source-map-loader.js'
+                    ),
                     options: {
-                      plugins: () => [postcssPresetEnv({ stage: 0 })],
+                      // eslint-disable-next-line no-undefined
+                      sourceMap: undefined,
                     },
                   },
                 ],
@@ -603,9 +607,9 @@ describe('"sourceMap" option', () => {
       );
       const stats = await compile(compiler);
 
-      expect(
-        getModuleSource('./source-map/basic.postcss.css', stats)
-      ).toMatchSnapshot('module');
+      expect(getModuleSource('./source-map/basic.css', stats)).toMatchSnapshot(
+        'module'
+      );
       expect(
         getExecutedCode('main.bundle.js', compiler, stats)
       ).toMatchSnapshot('result');
@@ -613,28 +617,35 @@ describe('"sourceMap" option', () => {
       expect(getErrors(stats)).toMatchSnapshot('errors');
     });
 
-    it('should not generate source maps when source maps is valid from an other loader (`sass-loader`)', async () => {
+    it('should not generate source maps when previous loader generates source maps', async () => {
       const compiler = getCompiler(
-        './source-map/basic-scss.js',
+        './source-map/basic.js',
         {},
         {
           module: {
             rules: [
               {
-                test: /\.s[ca]ss$/i,
+                test: /\.css$/i,
                 use: [
                   {
                     loader: path.resolve(__dirname, '../src'),
-                    options: {
-                      sourceMap: false,
-                    },
+                    options: { sourceMap: false },
                   },
                   {
-                    loader: 'sass-loader',
+                    loader: path.resolve(
+                      __dirname,
+                      './fixtures/source-map-loader.js'
+                    ),
                     options: {
-                      // eslint-disable-next-line global-require
-                      implementation: require('sass'),
-                      sourceMap: true,
+                      sourceMap: JSON.stringify({
+                        foo: 'bar',
+                        version: 3,
+                        sources: ['basic.css'],
+                        names: [],
+                        mappings: 'AAAA;EACE,UAAU;AACZ',
+                        file: 'basic.css',
+                        sourcesContent: ['.class {\n  color: red;\n}\n'],
+                      }),
                     },
                   },
                 ],
@@ -645,7 +656,7 @@ describe('"sourceMap" option', () => {
       );
       const stats = await compile(compiler);
 
-      expect(getModuleSource('./source-map/basic.scss', stats)).toMatchSnapshot(
+      expect(getModuleSource('./source-map/basic.css', stats)).toMatchSnapshot(
         'module'
       );
       expect(