i upload the mod "OptiFabric" to my game and when i join a multiplayer server, a black screen appear please fix it or tell me hwo to fix it

MC version, which launcher, list of mods being used AND their versions?

MC version, which launcher, list of mods being used AND their versions?

Bro I just use feather client and the optimise fabric mod on feather do the same thing as Optifabric mod

Without either an error log OR the Minecraft Version, Mods used WITH their versions it is hard to provide you support.