Some modern skins may not draw correctly with either partial or completely missing window frames or flashing elements. This seems to be due to a change made on Feb 20th in the interim / beta builds to resolve seeker bar elements along with some other elements not showing as expected in the skins. A solution to keep the prior fix & un-break the skins now being reported as broken is being looked into.
The send-to menu action may crash for some setups due to handling issue with the library playlists plug-in whilst the library core is trying to determine which plug-in handles the selected action.