I noticed this problem after I switched to Linux, but I'm not sure if it's because of the OS change, because after that the browser had several major updates and Construct3 itself changed the version.
I see it this way: sometimes when I open a project file, the editor buttons become unclickable, I wait a few seconds, and if it doesn't go away, I just close this tab and open the project in a new browser tab.
It doesn't happen regularly, and I can't sit and open all day to catch it.
Platform information
Product: Construct 3 r440.2 (stable)
Browser: Chrome 137.0.7151.68
Operating system: Linux 6.8.0