Thanks for providing this image (vf2-debian13-20250320.img.xz).
I have uploaded it to Mega.
I tested playing a 1080p h264 video file with Firefox, and it looks like it does use the VPU (hardware video decoding). I wasn’t able to install the extension enhanced-h264ify, so I wasn’t able to test it with YouTube.
I activated the apt source in /etc/apt/sources.list.d/debian.sources but sudo apt upgrade removed the hardware acceleration.
I’m going to continue testing.