Comment # 45 on bug 1221531 from Nikolai Nikolaevskii

(In reply to Andrei Borzenkov from comment #19)
> (In reply to Andres Nogueiras from comment #18)
> > mozilla-nss: 3.98-lp155.1.2
> 
> Where does it come from?
> 
> andrei@leap155:~> zypper se -sx -t package mozilla-nss
> Loading repository data...
> Reading installed packages...
> 
> S | Name        | Type    | Version              | Arch   | Repository
> --+-------------+---------+----------------------+--------+------------------
> -------------------------------------------
> i | mozilla-nss | package | 3.90.2-150400.3.39.1 | x86_64 | Update
> repository with updates from SUSE Linux Enterprise 15
> v | mozilla-nss | package | 3.90.1-150400.3.35.2 | x86_64 | Update
> repository with updates from SUSE Linux Enterprise 15
> v | mozilla-nss | package | 3.90-150400.3.32.1   | x86_64 | Update
> repository with updates from SUSE Linux Enterprise 15
> v | mozilla-nss | package | 3.79.4-150400.3.29.1 | x86_64 | Main Repository
> andrei@leap155:~>

Leap uses Firefox ESR by default. To get newer ones user needs to add Mozilla
repo:
zypper addrepo
https://download.opensuse.org/repositories/mozilla/openSUSE_Leap_15.5/mozilla.repo

Package mozilla-nss 3.98-lp155.1.2 was retracted. Newer mozilla-nss
3.98-lp155.2.1 solves problems with addons. 

I didn’t touch FF 123 for a couple of days, used FF ESR. After installing
mozilla-nss 3.98-lp155.2.1 for Leap 15.5 addons for FF 123 started to work
without reinstall, for FF ESR I made uninstall + install to get rid of warnings
(with losing settings).
For some addons you can perform Backup + Restore settings (NoScript, uBlock
Origin, etc.).
Soon we will get FF 124, possible it will help with addons troubles.