diff --git a/docs/guide/custom-vue2-app-scan-selector.md b/docs/guide/custom-vue2-app-scan-selector.md
new file mode 100644
index 000000000..86134a197
--- /dev/null
+++ b/docs/guide/custom-vue2-app-scan-selector.md
@@ -0,0 +1,12 @@
+## Customize vue2 app scan selector
+> For example, if you are using micro-app as your micro-frontend framework, the devtools cannot find Vue2 apps in `<micro-app>` by default.
+
+You can set a custom selector used to scan for Vue2 apps in your project with the following code in your frontend app:
+
+```js
+if (process.env.NODE_ENV !== 'production') {
+  window.VUE_DEVTOOLS_CONFIG = {
+    customVue2ScanSelector: 'micro-app'
+  }
+}
+```
\ No newline at end of file
diff --git a/packages/app-backend-core/src/app.ts b/packages/app-backend-core/src/app.ts
index 125844db1..a5b7de850 100644
--- a/packages/app-backend-core/src/app.ts
+++ b/packages/app-backend-core/src/app.ts
@@ -26,7 +26,7 @@ export async function registerApp (options: AppRecordOptions, ctx: BackendContex
 
 async function registerAppJob (options: AppRecordOptions, ctx: BackendContext) {
   // Dedupe
-  if (ctx.appRecords.find(a => a.options === options)) {
+  if (ctx.appRecords.find(a => a.options.app === options.app)) {
     return
   }
 
@@ -194,15 +194,25 @@ export async function sendApps (ctx: BackendContext) {
   })
 }
 
+function removeAppRecord (appRecord: AppRecord, ctx: BackendContext) {
+  try {
+    appIds.delete(appRecord.id)
+    const index = ctx.appRecords.indexOf(appRecord)
+    if (index !== -1) ctx.appRecords.splice(index, 1)
+    removeLayersForApp(appRecord.options.app, ctx)
+    ctx.bridge.send(BridgeEvents.TO_FRONT_APP_REMOVE, { id: appRecord.id })
+  } catch (e) {
+    if (SharedData.debugInfo) {
+      console.error(e)
+    }
+  }
+}
+
 export async function removeApp (app: App, ctx: BackendContext) {
   try {
     const appRecord = await getAppRecord(app, ctx)
     if (appRecord) {
-      appIds.delete(appRecord.id)
-      const index = ctx.appRecords.indexOf(appRecord)
-      if (index !== -1) ctx.appRecords.splice(index, 1)
-      removeLayersForApp(app, ctx)
-      ctx.bridge.send(BridgeEvents.TO_FRONT_APP_REMOVE, { id: appRecord.id })
+      removeAppRecord(appRecord, ctx)
     }
   } catch (e) {
     if (SharedData.debugInfo) {
@@ -212,9 +222,17 @@ export async function removeApp (app: App, ctx: BackendContext) {
 }
 
 // eslint-disable-next-line camelcase
-export async function _legacy_getAndRegisterApps (Vue: any, ctx: BackendContext) {
+export async function _legacy_getAndRegisterApps (ctx: BackendContext) {
+  // Remove apps that are legacy
+  ctx.appRecords.forEach(appRecord => {
+    if (appRecord.meta.Vue) {
+      removeAppRecord(appRecord, ctx)
+    }
+  })
+
   const apps = scan()
   apps.forEach(app => {
+    const Vue = app.constructor
     registerApp({
       app,
       types: {},
diff --git a/packages/app-backend-core/src/index.ts b/packages/app-backend-core/src/index.ts
index 66ba75431..58fda5927 100644
--- a/packages/app-backend-core/src/index.ts
+++ b/packages/app-backend-core/src/index.ts
@@ -61,14 +61,14 @@ export async function initBackend (bridge: Bridge) {
 
     if (hook.Vue) {
       connect()
-      _legacy_getAndRegisterApps(hook.Vue, ctx)
-    } else {
-      hook.once(HookEvents.INIT, (Vue) => {
-        _legacy_getAndRegisterApps(Vue, ctx)
-      })
+      _legacy_getAndRegisterApps(ctx)
     }
+    hook.on(HookEvents.INIT, () => {
+      _legacy_getAndRegisterApps(ctx)
+    })
 
     hook.on(HookEvents.APP_ADD, async app => {
+      await _legacy_getAndRegisterApps(ctx)
       await registerApp(app, ctx)
 
       // Will init connect
diff --git a/packages/app-backend-core/src/legacy/scan.ts b/packages/app-backend-core/src/legacy/scan.ts
index ed5481165..bdb73a7fc 100644
--- a/packages/app-backend-core/src/legacy/scan.ts
+++ b/packages/app-backend-core/src/legacy/scan.ts
@@ -1,4 +1,5 @@
 import { isBrowser, target } from '@vue-devtools/shared-utils'
+import { getPageConfig } from '../page-config'
 
 const rootInstances = []
 
@@ -60,6 +61,17 @@ export function scan () {
         // Ignore
       }
     }
+
+    // Scan for Vue instances in the customTarget elements
+    const { customVue2ScanSelector } = getPageConfig()
+    const customTargets = customVue2ScanSelector ? document.querySelectorAll(customVue2ScanSelector) : []
+    for (const customTarget of customTargets) {
+      try {
+        walkDocument(customTarget)
+      } catch (e) {
+        // Ignore
+      }
+    }
   } else {
     if (Array.isArray(target.__VUE_ROOT_INSTANCES__)) {
       target.__VUE_ROOT_INSTANCES__.map(processInstance)
diff --git a/packages/app-backend-core/src/page-config.ts b/packages/app-backend-core/src/page-config.ts
index cdca3acf0..42b627a3e 100644
--- a/packages/app-backend-core/src/page-config.ts
+++ b/packages/app-backend-core/src/page-config.ts
@@ -3,6 +3,7 @@ import { target, SharedData } from '@vue-devtools/shared-utils'
 export interface PageConfig {
   openInEditorHost?: string
   defaultSelectedAppId?: string
+  customVue2ScanSelector?: string
 }
 
 let config: PageConfig = {}