Hi..
Please add the rounded corners and borders to the PIP window, like almost all other browsers already have.
It seems that this floating window is the only thing in Firefox that does not follow the system rules (windows 11 in this case).
Right now this can be done in CSS, but there is a problem with the background window, which remains with square corners and this cannot be modified with just CSS..
Well, at least I could not find the way how to deal with this problem.
As a positive moment, this can also help those users who switch from Chrome to Firefox, as they could get used to seeing pip player like that..