Mod version: 2.0.7
Screenshots

Thank you for your report!


As the screenshots show, I cannot reproduce this. It's most likely caused by the the mod you have, that adds the 3D render at the top

I found a reason. The FPS decline came from The One Probe's entity model render. When hidden (enter /topneed, then click Needed), The FPS became normal. Instead of large entity model.
I don't know how to close entity model render for The One Probe mod.

Oh it's The One Probe? You're right that is quite a huge FPS drop, I'll see if I can do anything on our side (Since it does not happen for vanilla wolfs)

Fixed by 9c26ea9
Turned out to be a super weird cause, but managed to find a workaround (Thanks to @lclc98)
The One Probe might be creating a new entity when doing the 3D rendering, which is a bad thing..
But yea at least the FPS drop is completely gone now.