Welcome back ale5000!
I have joined the forum and the scripting VLC in Lua at the time you disappeared several years ago. I like the idea of extending the VLC functionality using custom scripts to implement specific features that would be barely built into VLC's core. I have learnt also from your scripts and even tried to improve your Subtitles finder extension. The topic about the obsolete extension is still pinned here.
The Exebetche's VLSub extension has been included in VLC 2.1. Later after changes on opensubtitles.org and malfunction of the extension, VLC developers have decided to fix and improve VLC's own fork of VLSub and recently VLC 3.0.2 has introduced new vlc.io functions solving the issue with non-ASCII characters in paths (UTF-8 strings) within Lua's standard io functionality.
You should check the current
README.txt and its history. Since VLC 2.1, vlc.misc is available only for Interfaces, datadir/userdatadir/homedir/configdir/cachedir are now available within vlc.config, vlc.var.add_calback useful for "dynamic" Extensions was removed and vlc.net module was not available for Extensions at that time. Since VLC 3 the vlc.var.get/set time variable is in microseconds instead of seconds in older VLC versions. Lua scripts should have a better stability in current VLC.