MWA not working on mobile Firefox

[d-reader-josip]

Previous discussion: #345 (comment)
This issue has been submitted in order to raise awareness and track progress (if any) on it.

Has something to do with Firefox mobile browser suspending execution the moment the browser is backgrounded

[sdlaver]

Can reproduce the issue. What to do about it is harder. A fix for Firefox on Android will likely rely on installing some kind of extension, that plays the same role for Mobile Wallet Adapter connections as this extension does for video playback: https://github.com/mozilla/video-bg-play

Also worth investigating: whether any of the throttling exemptions listed here would be effective: https://developer.mozilla.org/en-US/docs/Web/API/Page_Visibility_API#policies_in_place_to_aid_background_page_performance

[d-reader-josip]

What about startForegroundService? https://stackoverflow.com/questions/52458942/websocket-disconnection-of-the-user-android-ios-during-the-app-in-background-a

Also, it makes sense to work out this issue even though there is only a handful of mobile firefox users. One day Chrome might add a similar policy on mobile to optimize performance which would deny MWA and require a similar fix. So best to resolve this sooner rather than later and apply a similar fix to mobile Chrome if necessary?

[Funkatronics]

@d-reader-josip there would not be any way to start a foreground service from a webpage on Android. The webpage running in Firefox does not have access to the native Android SDK that Firefox is running on (unless Firefox provides some kind of wrapper? doubtful).

The wallet app could start a foreground service, but the webpage in Firefox would still not be able to connect to and communicate with it if Firefox is in the background.

I agree with @sdlaver that an extension running in Firefox is likely a solution. Worth investigating:

• running a websocket in an extension background script, and see if it is paused when Firefox is backgrounded
• the video extension that Steven linked uses a couple tricks like blocking the page visibility change events from propagating, and simulating user input to keep a video from pausing. Might be worth trying these tricks out to keep the websocket alive