I can't reproduce this myself with a new file, but I do have proof that it can and has happened. I don't know what specifically caused/causes it. I'll provide as much detail as I can. I worked for about 5 hours on a drawing, with recording enabled. It produced about 2700 drawings in the KritaRecorder folder. The next day I opened the same file again, made sure the recorder was running, and finished the picture in another 5 hours. When I exported the timelapse, only the first session was saved. I searched, but it appears that Krita did not save any timelapse snapshots for the entire second session despite the recorder stating that it was running. The entire second session was recorded with OBS, and the recorder docker is visibly greyed out with a 'stop' button through the entire session. The bottom 'recording' green/red dot is also visible, but notably- the green dot did not turn red for the entire 5 hours of drawing. Something I didn't notice until I rewatched the recording.
There is a bug on current master where opening another document while recording is on stops all recording, while still showing it enabled (https://invent.kde.org/graphics/krita/-/merge_requests/2118). Could that have been the cause here?
(In reply to Freya Lupen from comment #1) > Could that have been the cause here? That does seem plausible, I rewatched the recording but unfortunately it started after I had already supposedly just opened the file. It's possible that right before the recording I may have created or opened a document and then closed it. I'll keep that in mind when I'm on master. I recreated the bug you were talking about, and the symptoms seem to be the same- green dot never turns red, but docker appears as if it's recording.
The above MR was merged and this problem hasn't happened since, marking as fixed.