30 - which should be enough for more than 1MB i think…
There’s also a max_allowed_packet setting you might want to experiment with
Isn’t this for MySQL?
What is your PHP version? Kirby version? Browser?
7.1.11 and 2.5.7, Safari and Chrome.
Another thing i am thinking about is this default Plesk nginx Proxy Configuration, because i’m not very experienced with this and don’t know if this could affect file upload…