Hold Alt ...
when you click the "Product" menu.
You will get a "Clean Build Folder".
(If you forgot the curse key, just type “Clear” in the search field in the “Help” menu.) Is that what you need? Hope this helps ...
It seems strange that it takes 20 minutes, which does not seem normal. Are you in Workspaces on X4? (Perhaps this is relevant - I do not know.)
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