Since updating to 3.0, I'm getting this quite often - when I arm a behavior, the Scene view goes blank with "Preparing Scene". If I close the program and reopen, then I can continue, but in this particular session it's getting to where it does this every few minutes. Has anyone else experienced this?
I've been running into this issue as well during recording. I'm making revisions to the takes and the interface pauses with a messsage "preparing scene." I've been recording with multiple triggers and behaviors turned-on at the same time. When going back and deleting takes I don't want to use, the scene window refreshs with each new adjustment. This was slowing down my workflow. My work around is to close the scene window while making these edits. After closing the window, I was able to adjust the length of handles without waiting for the scene to refresh. Then go to Window > Scene to reopen the scene panel.