is this supposed to happen?

I also have this problem
mod version: 1.8.9-2.1.1.136
mc version: 1.8.9
forge: 1.8.9-11.15.1.2318
Uteam Core: 1.8.9-1.3.0.63

No that's not supposed to happen.
What's your minecraft version?

It's generally a good idea to follow the bug report template

Seems like this is a duplicate of #55 (Issue with optifine probably)
As 1.8.9 is too old this will probably not be fixed. In the linked issue there is a resource pack that you can use to fix that issue.