Google may try to enforce MV3 on Firefox. 90% of Mozilla's income comes from Google and while Google needs this controlled opposition, they may lower their input to almost-suffocate Mozilla whenever they desire.
https://www.ghacks.net/2022/09/24/mozilla-reaffirms-that-fir...
Now that they have Edge, they need neither. Because they can now pretend that Edge is something else but a glorified Chrome fork and follower.
See, for example, WebTransport which as a standard doesn't even exist beyond some scribbles on a napkin https://web.dev/webtransport/
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The WebTransport features described in this article are shipping in Chrome, Edge, and other Chromium-based browsers, starting with version 97.
Firefox does not currently have support for WebTransport. Updates on their position can be found in this GitHub issue.
Safari does not currently have support for WebTransport.
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