What is the most efficient, yet most foolproof way for us to explain to another user how to follow through with this downgrade?
The method that I followed was:
- remove 5.10.x versions of kmod-mwlwifi, kmod-mac80211, kmod-cfg80211
- install 5.7.5 versions of kmod-mwlwifi, kmod-mac80211, kmod-cfg80211
- manually install mwlwifi-firmware-88w8964_* firmware blob
- reboot router
My method was successful. However, based on dependencies, I lost the mwlwifi-firmware-88w8964_* firmware blob package along the way and that is why I had to manually install that. It's likely that my router would have crashed if I rebooted without first noticing that firmware blob missing.
So would it be smarter (and more foolproof) not to uninstall anything manually and simply use the --force-reinstall flag as part of the opkg install command?