It was clearly a Nazi salute.
plenty of videos of that you can find online.
So those don't count, because?
Before and after unedited context of Elon clearly shows him throwing "a Roman salute" twice.
Highly edited footage of Bernie Sanders holding his arming up in greeting as he turns and greets and waves to a crowd is nothing like the gesture made by Elon .. and with a proper unedited context even less so.
At least try and provide better footage to support your claim.