@Hölzl, Dominik -
The use of browser extensions with native messaging in the WebView2 control within the Teams desktop client is not supported.
The Teams desktop client does not expose the WebView2 control for use with browser extensions.
The WebView2 control is primarily intended for use in custom Windows applications to host web content, and its integration with browser extensions is not supported within the Teams platform.
Thanks,
Nivedipa
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