playing with some mods here, I experienced a very bothering "flicker" of the side-meu when u have some mods altering the entities.
Below the entityname in the sidepanel on the right hand side there is a yellow line telling me which mods are active on this entity.
- And if this line is to long, the panel just extends its width instead of using multiple lines or [...] and opting for a tooltip.
This results in a moving sidepanel whenever u hover over such entities - especially frustrating with trees:

