[web] force WebGL 1 on iOS

[yjbanov]

This is a workaround for the issue described in flutter/flutter#91333.

Fixes flutter/flutter#89655

[flutter-dashboard]

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[ditman]

LGTM! Also: easy to delete.

[technolion]

Is this going to be pulled into a stable 2.5.4 release?

[aytunch]

Our web app does not work on iPhone 13 Pro with iOS 15
Will this be added to the stable channel soon?
Also using WebGL 1 is not a real solution right? Is there a PR or issue which works on WebGl2 support?

[adrianjagielak]

Our web app does not work on iPhone 13 Pro with iOS 15
Will this be added to the stable channel soon?
Also using WebGL 1 is not a real solution right? Is there a PR or issue which works on WebGl2 support?

Try this: flutter/flutter#89655 (comment)

[technolion]

I just checked: this PR now part of the current flutter stable (2.10.1) 🎉

[theAugur]

Is this on stable? I am still getting this problem with stable 2.10.2... My web app won't work on iOS safari unless I build it with: flutter build web --web-renderer html --release

[daonb]

iOS 15.4 fixed the safari bug and WebGL rendering works as it should.