Is that a new thing that there's a popup when I select text with the mouse? In like 33% of the times, I end up copy/pasting the content of the popup instead of the text I just selected.

Yep: https://blog.jetbrains.com/idea/2023/10/intellij-idea-2023-3-eap-3/#code-editing-actions-available-via-floating-toolbar

Aaahh just what I was looking for, thank you! thank you color