This file is actually corrupted and crashes in earlier versions of blender when you try to delete strip or hit TAB. Quite the same setup already happened once but we really need to know steps of reproducing such situation. Do you remember what did you do with this file or maybe you'll be lucky enough to reproduce the issue with fresh file?

I've found a solution to the immediate problem. Making a copy of the scene will work and fix the problem. The original scene can be deleted and the new scene renamed to the original scene's name, so everything is back to normal.

I'm not sure what I might have done to create this situation. It might have to do with creating and deleting metastrips. I will try to be aware of anything I do that leads to this problen in the future.

Tony, it's not about being aware and trying to avoid something, it's more about figuring out what exactly leads to buggy setup and fix issue here. It's quite a large bunch of code where issue could happen, so help from user side figuring out steps to reproduce bug will help a lot.

I will close the report since you already found a workaround, but please let us know if you'll manage to reproduce this bug.

Hi,

Thank you. I didn't mean that I'd be aware and try to avoid it. I meant that I would try to be aware so that I had a better idea of what steps led to the problem if it occurs again. I have not managed to reproduce this problem in simple examples. Of course I'll report if I can reproduce it.

Not-very-helpful side note: I had another similar file which had been worked with similarly in the past, but instead of crashing on delete, Ctrl+Z ceased to work on only that scene. The same workaround (copy scene) worked in this instance as well, and Ctrl+Z worked again. In this case, I *was* able to delete strips without Blender crashing.

Anyway, I'll let you know if I can reproduce it from scratch.

T