You can import YouTube subscriptions by clicking on the Sources tab and then tapping on the YouTube source (says tap to open in small print). You can then sign in and after that you’ll have import subscriptions as well as import playlists buttons.
It’s important to know what’s going on when the computer cuts power. I had this start happening to me when I was playing VR games. I had been using the same hardware to do so for a year beforehand, but it turns out I was just riding the limit of what the PSU could supply. When I actually took a look at how many watts the UPS was reporting it was happily under the PSU’s rating, however Nvidia GPUs are known to power spike at times and draw way more power than they’re supposed to. That’s what was causing my issues. An upgraded PSU indeed fixed everything.
Check out the slow mo guy’s video on this https://youtu.be/0srs5jZ1qdg?si=HWTzB_aOFXMO2OB-