Currently, every package update of Jitsi overwrites all language files in /usr/share/jitsi-meet/lang reverting all changes the local administrator has done to localize the instance of Jitsi.
This could be solved by checking for the existance of and then reading a local version of the language file, for example
Such a file should only contain those language strings the administrator wants to change, the original language file should kept unchange and can this easily be updated/overwritten by an update.
From a developers perspective, this handling would just require a conditionally executed second run of the language file import function during which preserves existing language strings and only overwrites those in the local file.
This kind of approach is a usual way to localize configurations.