VLsub unable to download subtitle due to cache folder missing
First reported here: https://github.com/exebetche/vlsub/issues/213
On certain Linux distributions (for me Kubuntu 18.10), VLsub fails to download any subtitle, and instead report the error to the user who is redirected to download it rom the opensubtitles website.
As reported in that link, the problem is that vlc does not create the cache folder, and the workaround is to create it manually
mkdir ~/.cache/vlc
My VLC version is 3.0.4