fix: clarify error message

closes #10109

Author: dummdidumm

packages/svelte/src/compiler/errors.js

@@ -78,7 +78,7 @@ const parse = {
 	 * @param {string} reason
 	 */
 	'invalid-closing-tag-after-autoclose': (name, reason) =>
-		`</${name}> attempted to close element that was already automatically closed by <${reason}>`,
+		`</${name}> attempted to close element that was already automatically closed by <${reason}> (cannot nest <${reason}> inside <${name}>)`,
 	'invalid-dollar-binding': () =>
 		`The $ name is reserved, and cannot be used for variables and imports`,
 	'invalid-dollar-prefix': () =>

packages/svelte/tests/compiler-errors/samples/unmatched-closing-tag-autoclose/_config.js

@@ -3,7 +3,8 @@ import { test } from '../../test';
 export default test({
 	error: {
 		code: 'invalid-closing-tag-after-autoclose',
-		message: '</p> attempted to close element that was already automatically closed by <pre>',
+		message:
+			'</p> attempted to close element that was already automatically closed by <pre> (cannot nest <pre> inside <p>',
 		position: [24, 24]
 	}
 });