PostmarketOS is amazing on supported arm chromebooks. Unfortunately the newest 'community' level supported devices are all from the early 2020's and are getting a bit long in the tooth, especially when it comes to web browsing. I have a few that I throw in a bag for beach/jungle holidays - they are literal e-waste, something liberating about carrying a laptop that's worth significantly less than a decent family meal.
"Another issue is that this device is working well enough in v25.12 release, but I tried edge once (the rolling release channel) and my touchpad started to work in absolute instead of relative mode."
I (foolishly) did an apk upgrade and ran into this one - an AI fixed it for me, its caused by keyd having a too broad device mask (0000:0000) so it grabs everything including the touchpad causing havok. From my noteslop: "The fix was to patch /usr/bin/pmos-generate-cros-keymap to match the exact cros_ec keyboard ID, k:0000:0000:af5c732c, then regenerate the config and restart keyd so it no longer grabs the touchpad. "