I can not load some http2 pages with the newest firmware versions 07.04.4 and 07.04.3 via my RUT360. I get the http2 protocol error in different browsers (chrome, brave) on my android device (Androi 13, one ui 5.1). Clearing browser cache did not have any effect. After downgrading to 07.02.2 everything works properly again.
I connected with a Samsung Tablet S7 (SM-T875) to the RUT 360 via WiFi.
Are you sure the browsers are up to date? No such issues have been reported before.
Also, could you clarify the device you are using to connect to the router?
Could you try a browser like Firefox (or anything else not based on chromium)?