This happens to me all the time and is for sure unexpected. I create some sketches and objects then I hide them because I want to use them later and don’t want to mess them up. When I draw something those re-appear even though they should be hidden.
In this video, I made an outline of an ESP32. I put that in a folder and hid the folder.
Then I started drawing something else. When I draw the line the hidden folder re-appears.
How can I stop the hidden things from becoming un-hidden?