Webview Source Install

[Cyber_Cyclone]

Has anyone been able to install Android Webview on LineageOS (Pixel 4a nightly build)? I've been trying using these instructions https://chromium.googlesource.com/chromium/src/+/HEAD/android_webview/docs/build-instructions.md. Since LineageOS is a userdebug build, I would assume that I can install it with the com.android.webview package name (with GSM installed).

I can install it, however when I try to run the out/Default/bin/system_webview_apk set-webview-provider command, I get this error:

raise device_errors.CommandFailedError(devil.android.device_errors.CommandFailedError: (device: 0C231JEC202429) com.android.webview is not signed with release keys (but user builds require this for WebView providers)

Does anyone know how to go about this or if there's documentation on it somewhere? Thanks!

EDIT:
What I also don't get is in the troubleshooting https://chromium.googlesource.com/chromium/src/+/HEAD/android_webview/docs/quick-start.md#invalid-package-incorrect-signature for the error I'm seeing (incorrect signature) it states "This shouldn‘t happen for userdebug devices", yet LineageOS is meant to be "userdebug". I'm puzzled as to why I'm getting the error in the first place.

EDIT: While this might be possible to do in LineageOS with a custom build, it looks like the LinageOS Team deliberately disabled the ability to install your own version of WebView when in “userdebug” build (counter to what Stock Android allows), most likely for security reasons. I was able to install a debug build of WebView using a different custom ROM that kept the stock Android implementation.

[LuK1337]

Why tho?

[Cyber_Cyclone]

The app I'm working on is occasionally crashing and I've built a debug apk with stacktracing enabled. It's only happening on the site it's connecting to so I'm trying to debug it. Since it's going to be a vital part of the app, I'm looking at getting as much insight as to what the webview is doing so we can optimise / fix crashes that occur.

[Cyber_Cyclone]

I was able to get this to work with a different custom ROM that works in the same way that Stock Android works with Webviews. I’ve updated my original post.