We're playing on a server, and whenever someone dies, log in to the server or logout we lose the flight buff for 10-20seconds.
(We're on a skyblock world, losing flight isnt very fun, can lead to more deaths and more time without fly buff, is like a chain reaction of ppl dying lol)

This mod is merely enabling creative-mode flight. So if this breaks, this would mean that some other mod in your pack is disabling flight on death/(dis)connect. There's unfortunately not much I can do about that on my end.

The only thing you could do as far as I can see is going through your modlist, and disabling them one-by-one to find the offending mod.

Ok, should you be able to figure out what mod is causing it, be sure to let me know :-)

Thanks for the fast reply rubensworks, not sure if i want to try that with 200+ mods, will take ages. We'll just keep enjoying our death chain reaction for now XD