On my website, when I try to do a WordPress image upload I get http error. Normally I’d think this was a PHP error, but all seems fine on my server.
When I switched back to Twenty seventeen theme it works fine.
Then, back to GPP and all seems fine at moment. Not sure if I’m losing it, but first time I’ve had this issue. It’s only an issue if I upload from Dokan multi vendor front end control panel, not from backend. Obviously I’d be more inclined to think it’s a Dokan issue, but all cleared up when using default Wp theme.