video – Quicktime 1-hour screen recording only lasts 15 minutes

I used Quicktime to record my screen for approximately 1 hour. When then hour passed, I clicked the stop recording button in the menu bar. The video took a looong time to pop up, around 30 – 40 minutes. However when I see the recording, it is only 15 minutes long.

I was reading and there is this energy saving setting that stops the video after 15 minutes, but my video didn’t stop, I had to stop it myself and I did so after an hour. It also took a long time to process which could be an indication of processing a long video. So, what happened to the rest 45 minutes of it?

I am using Big Sur.

I checked the unsaved documents folder and it is empty. Is there a way to get the complete video or is it lost forever. Has anyone experienced something similar?
Any inputs would be appreciated.

Thanks.

EDIT: after some testing it seems that indeed the energy saving option was causing the videos to stop. Still looking for some input if the rest of the recording can somehow be found anywhere, as like I mentioned before, the recording (at least the interface) was still running for the whole hour plus the processing time was super long.