I have a Joomla website (which I didn't install myself) that seems to be lacking the system plugins "Language Filter" and "Language Code". It seems like it wasn't installed as a multi-language site in the first place (I assume) so that might explain why these two plugins are missing (or maybe that I just fail to find them).
My question is : how can I install these two plugins on an existing Joomla website ?
I am using Joomla 3.8.7
Ok my bad, they were installed. I failed to find them because their names were translated into French in the administration panel...