Can the PPP play HD videos?

[megous]

The keyboard is working again with the latest update.  The fn/symbol keys don't initially work, but can be fixed with the information at: https://wiki.mobian-project.org/doku.php...ccessories

I was talking about decoding by special HardWare on the SoC. When that's not available, decoding happens on the CPU.
Then, the power of the CPU determines which resolution is can decode (without dropping frames etc).

Yes, got it. The question remains then: Is the hardware powerfull enough...?

Both Pinephone and Pinephone Pro can play H.264 encoded videos (using ffmpeg or gstreamer based apps) at FullHD with no issues at 60 FPS, and with rather small power consumption. You just need to install libraries that support HW decoding https://wiki.pine64.org/wiki/Mainline_Ha...ing#FFmpeg

Either ask your distro maintainers to package the proper versions or install them yourself via the above guide. Kernel supports the drivers for video decoders for years, no need to do anything there.