Right now when you resize the PiP it is locked to the aspect ratio of the original video. I would like to have the option to freely resize the PiP (and for FF to remember the setting!) so I can save space.
I think this the right enhancement for this feature. PiP is by design made for multi-tasking. Sometime I have a hard time finding a good spot for the PiP. I have to resort to tricks like moving part of the video off-screen. You have most likely done the same at some point.
Having the option to freely resize the video would free up valuable space on screen without sacrificing too much information. Instead of (or in addition to) freely resizing Firefox could offer space-saving aspect ratios like 14:9 or 4:3. Cutting off the outer edges of the video image which usually don't contain important information would be a nice trade-off for gaining more usable space on the desktop.
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