Kovid,
I have some unknown property names in CSS when I do a check for:
panose-1:
Hyphenation: adobe-hyphenate, hyphens, -moz-hyphens,, -webkit-hyphens
An other observation:
When I move the inspector window with the mouse the window flips back to the old position. I think, it will be a better choice to have no moving or undock for this window, as long as the window will lose the content by doing this (only a guess).