Unable to render iframe content

Why I can't render the following content, if I use the same url, it works in my browser.

```
**Content:**

String toLaunch = 'https://human.biodigital.com/widget/?be=2bMX&initial.hand-hint=true&ui-info=true&ui-fullscreen=false&ui-zoom=true&ui-share=false&uaid=2nrfe';

Launching lib\main.dart on SAMSUNG SM N900A in debug mode...
Initializing gradle...
Resolving dependencies...
Running 'gradlew assembleDebug'...
Built build\app\outputs\apk\debug\app-debug.apk.
pLocation:automatic, pLang: , pRegn:

pLocation(NoSIM):english_us, pLang: en, pRegn: US

Installing build\app\outputs\apk\app.apk...
I/FlutterActivityDelegate(19106): onResume setting current activity to this
Syncing files to device SAMSUNG SM N900A...
D/ViewRootImpl(19106): ViewPostImeInputStage ACTION_DOWN
D/ViewRootImpl(19106): ViewPostImeInputStage ACTION_DOWN
D/ViewRootImpl(19106): ViewPostImeInputStage ACTION_DOWN
D/ViewRootImpl(19106): ViewPostImeInputStage ACTION_DOWN
D/ViewRootImpl(19106): ViewPostImeInputStage ACTION_DOWN
D/ViewRootImpl(19106): ViewPostImeInputStage ACTION_DOWN
I/Timeline(19106): Timeline: Activity_launch_request id:rubencg195.anatomika time:61620305
I/WebViewFactory(19106): Loading com.google.android.webview version 67.0.3396.87 (code 339608700)
D/ResourcesManager(19106): creating new AssetManager and set to /data/app/com.google.android.webview-1/base.apk
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/cr_LibraryLoader(19106): Time to load native libraries: 1 ms (timestamps 475-476)
I/chromium(19106): [INFO:library_loader_hooks.cc(36)] Chromium logging enabled: level = 0, default verbosity = 0
I/cr_LibraryLoader(19106): Expected native library version number "67.0.3396.87", actual native library version number "67.0.3396.87"
I/cr_BrowserStartup(19106): Initializing chromium process, singleProcess=true
I/cr_base (19106): Android Locale: es_US requires .pak files: []
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
I/art (19106): Rejecting re-init on previously-failed class java.lang.Class
E/libEGL (19106): validate_display:255 error 3008 (EGL_BAD_DISPLAY)
W/cr_media(19106): Requires BLUETOOTH permission
D/Activity(19106): performCreate Call secproduct feature valuefalse
D/Activity(19106): performCreate Call debug elastic valuetrue
W/AudioCapabilities(19106): Unsupported mime audio/evrc
W/AudioCapabilities(19106): Unsupported mime audio/qcelp
W/VideoCapabilities(19106): Unrecognized profile 2130706433 for video/avc
W/AudioCapabilities(19106): Unsupported mime audio/mpeg-L1
W/AudioCapabilities(19106): Unsupported mime audio/mpeg-L2
W/AudioCapabilities(19106): Unsupported mime audio/x-ms-wma
W/AudioCapabilities(19106): Unsupported mime audio/x-ima
W/AudioCapabilities(19106): Unsupported mime audio/amr-wb-plus
W/AudioCapabilities(19106): Unsupported mime audio/qcelp
W/AudioCapabilities(19106): Unsupported mime audio/evrc
W/VideoCapabilities(19106): Unsupported mime video/wvc1
W/VideoCapabilities(19106): Unsupported mime video/x-ms-wmv
W/VideoCapabilities(19106): Unrecognized profile/level 32768/2 for video/mp4v-es
W/VideoCapabilities(19106): Unsupported mime video/wvc1
W/VideoCapabilities(19106): Unsupported mime video/x-ms-wmv
W/VideoCapabilities(19106): Unsupported mime video/x-ms-wmv7
W/VideoCapabilities(19106): Unsupported mime video/x-ms-wmv8
W/VideoCapabilities(19106): Unsupported mime video/mp43
W/VideoCapabilities(19106): Unsupported mime video/sorenson
W/VideoCapabilities(19106): Unsupported mime video/mp4v-esdp
E/File (19106): fail readDirectory() errno=2
W/cr_CrashFileManager(19106): /data/data/rubencg195.anatomika/cache/WebView/Crash Reports does not exist or is not a directory
I/VideoCapabilities(19106): Unsupported profile 4 for video/mp4v-es
I/Timeline(19106): Timeline: Activity_idle id: android.os.BinderProxy@768f264 time:61621113
V/ActivityThread(19106): updateVisibility : ActivityRecord{390ce8e7 token=android.os.BinderProxy@26801bd4 {rubencg195.anatomika/rubencg195.anatomika.MainActivity}} show : false
D/ViewRootImpl(19106): ViewPostImeInputStage ACTION_DOWN
D/ViewRootImpl(19106): ViewPostImeInputStage ACTION_DOWN
```

まず、報告された Samsung デバイス上で、flutter_webview_plugin の example または別の最小限の Flutter アプリに報告された URL を再現します。次に、ブラウザーの動作と比較し、ここに含まれている Android WebView のログを調査します。iframe を plugin 経由でレンダリングできるかどうかを特定し、確認された差異を文書化または修正できれば完了です。

索引モデルが issue の本文から書いたものです。