This is local media stream on iOS 15(iPhone). This wasn't happened before iOS 15.

When I rotate phone, It fits in black area.

I tested it at https://webrtc.github.io/samples/src/content/getusermedia/gum/

The question is, How can I hide black background on portrait mode? I want it to be transparent.

CodePudding user response：

This is a known regression: https://bugs.webkit.org/show_bug.cgi?id=229792 The fix has already landed in webkit.