As of macOS 13.0 any audio now playing is shown in the Menu Bar with options to scrub, pause, and play. When using this feature in Firefox, the scrubber and times do not work, and thumbnails are not shown. All of this works in Chromium browsers.
As well, it would be useful if Firefox offered a built-in set of media controls in the Toolbar in the same way Chrome does.
Edit: Here's a screenshot of the Now Playing widget in Firefox vs Chrome.
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