In T90929#1296825, @Pratik Borhade (PratikPB2123) wrote:

Hi @Andrew M. (realandrew) , did you manage to get similar crash after reporting this bug?
There can be many reason for the crash. Crash logs may help to identify the problem: https://docs.blender.org/manual/en/dev/troubleshooting/crash.html#crash-log
We cannot help much without reproducing the issue.

That is interesting, when the crashes occurred for me I don't have any extra add-ons (not quite true I use an add-on called Unreal Right Click, but I don't think that was the cause for me). It seems perhaps this bug has multiple conditions that enable it to occur (compressed save files, certain add-ons, and something unknown which caused it for me). Still, the common factor is Windows (7/8/10/11) and Nvidia GPU, which means the bug is somehow related to that. I wish I could test more but I have trouble intentionally reproducing the bug, it usually crops up when I'm many minutes into a project, I haven't been able to get it to appear when scaling a cube many times and then undoing many times as you were able to.

@kursad k (kursadk) Unfortunately I haven't had any progress, we need a .blend that we know causes the crash so that the problem is somewhat reproducible. I haven't used Blender since reporting this bug due to being busy, but if you or anyone has a .blend saved that was open when the crash occurs if you could supply it here that would be great. Other than that, I think the problem is narrowed down to Windows (7/8/10) computers with Nvidia GPUs. One question I do want to ask for others who are experiencing this bug: Do you have Nvidia Geforce Experience installed? Not just the standard graphics control panel, but Geforce Experience (which lets you update your drivers and also has an in-game overlay and such). I'm wondering if maybe that is related to the crash in some way.

Some of the reports I saw were T61527, T22834, T39119, T60849, T68373, T54598, there are more you can find by googling for "blender ctrl-z closes program" or something similar. The common factor seems to be Windows (but not necessarily Windows 10, as some had Windows 8 as well) and Nvidia GPUs. This is likely some rare bug resulting from the combination of Windows + Nvidia + Blender, so that's likely why the bug hasn't been solved even though it seems to have existed for a while.

In T90929#1211552, @kursad k (kursadk) wrote:

The Blender file can be saved as a compressed .blend file. It is an option in the save window.

In T90929#1211540, @kursad k (kursadk) wrote:

I had this issue too. I traced it back to using compression for the Blender files, at least for the time being that seemed to be the issue. Do you happen to save your Blender file as a compressed file?