I've flashed my routers from 22.03.3 as issues with 5.15 kernel appear to have been mostly resolved.
However, I no longer have access to the router's LuCI provided by
luci-ssl, although the router's core functionalities remain working. I checked the system log through SSH and found it that
uhttpd is crashing.
It seems there are some changes in the encryption algorithms required for
uhttpd and the certificates previously generated on older versions of OpenWrt no longer works.
This issue is not device-specific. I've upgraded two devices of different architectures, and on both devices LuCI stopped working.
I don't know if there's an easy instruction on how to regenerate the certificates, and whether this needs to be done on an existing Linux PC or can be done entirely on the router itself...