In the Symbol Library Editor, if I duplicate (with the contextual menu item) a symbol which is an alias of a master symbol, all alias symbols referring to this master symbol are duplicated (which is not even visible if you filtered the view before duplicating). And removing a “duplicate” removes all of them in one go. Is it the expected behavior ?
Aliases don’t really exist, so when you copy and/or delete you’re copying or deleting the “master” symbol. The aliases are just some extra info stored there.
If you get a chance, click the “Does this bug affect you?” link here: