SystemExtr
Hello,
Should SystemExtr be erased from a MacBook or does the computer need it for something I am unaware of?
Question marked as
Should SystemExtr be erased from a MacBook ...
Yes.
Most likely, there are other files affecting that Mac that should be removed as in addition to it. For some background information please refer to Removing "Search Marquis" / "Search Baron" / etc on your own - Apple Community.