As mentioned in the topic, there is a problem with displaying tooltips. So far I have noticed this in the following mods: Mekanism, Cyclic. The details of the bug are shown in the video: https://imgur.com/a/aLLfhti

Logs:

• latest: https://gist.github.com/691a52c7eea7964ca004b88e0efdbabf.git
• debug: https://gist.github.com/d7cc7f9a15f901a0f45c24b27bcd9689.git

Versions:

• Minecraft: 1.16.5
• Forge: 36.2.39
• JEC: 1.9.2, there is also a problem with the version 1.9.0
• For ex. Cyclic: 1.5.18

Can confirm this issue in 1.18.2 with Simple Storage Network and Create.

Create goggle tooltip shows on top of inventory (hiding items behind it), and item names/info/button descriptions/etc are offset to the top left of the screen (like in the video linked by @DoctorSigma).

This affects Legendary Tooltips as well on version 1.18.2

Adding to this, in 1.16.5 this affects Tinker's Construct and Refined Storage as well.

Another add to this for 1.16.5, it also impacts Thermal Series among the others already mentioned above. Some of the above the tooltip is offset quite far to the left, Thermal doesn't show the tool tips at all (i.e. hover over power doesn't show how much RF etc).

Switching to an older version (3.8.6 the issue is not present). Only on the new version seemingly the widget might be the culprit.