a (hopefully temporary) pip solution for mac users
so, as i (we) wait for the coveted pip within plex media player,
i started researching chrome extensions for picture-in-picture
goodness (to no avail, it looks like they are all safari extensions).
in my searching i found a free app called helium (mac only).
it's a single window browser (no navigation from what i can tell)
that floats above all other windows, with optional transparency.
+el cap+yosemite users rejoice: you don't need sierra to run it.
it's not perfect, but it's 85% perfect.
(apologies if this should be in another forum. it's mac-specific+
addresses the pip wants of sierra (+as a bonus, slightly
under sierra) users.)