In the assembly drawing I'm working on, if I highlight a part instance and right-click, it no longer offers me 'activate part' or 'show instance' in browser or 'open to edit'. All it offers are pan, zoom, move, erase, copy, paste, etc. Other assembly drawings work fine. Is there a setting in Preferences that I somehow reset? I have searched high & low, I've opened the drawing on other workstations, it shows the same misbehavior there as well. TIA -doug