This is still currently an issue in version 29.11.29
I believe this is on the roadmap, and there might be other posts about it, but I’ll reiterate. I hope it’s fairly high on the priority list too. Currently, if you do hours of work within a filter, like adding many keyframes, and you press Undo or CTRL+Z, the entire filter and all your work will disappear, with no way to recover the loss. It’s extremely catastrophic to say the least.
My suggestion in the meantime is to save your Shotcut file VERY often, like every minute or 5 minutes at the very least. Or alternatively use Backup and Save, if you prefer to maintain a version history in case a file gets corrupted during save.
Basically, the undo does not support granular level things such as adding individual keyframes. It only supports much higher level actions like adding a filter.
I just lost quite a bit of work due to this very unfortunate weakness in the undo feature. Thankfully I have a good habit from long in the past of saving every so often, so I didn’t lose as much work as I might have otherwise.