Yet when I try to post a comment it will fail with language_not_allowed because initially there is no language selected. So I need to click on the "Select language" drop-down and choose English (the only option)
Actually in the Lemmy web interface (at least on my instance reddthat.com) the Post button will spin endlessly with no indication of what's wrong. Using the Jerboa Android app there's is the very brief error message language_not_allowed, and the comment disappears so I have to type it out again! On the Jerboa app there's also no option to select the language for the comment, so I can't use it to comment at all.
Is the language selected for posting comments the same setting as the profile setting, which the links recommend to keep as "undetermined" to be able to see (English language) posts?
Have i encountered a bug? Specific to my instance or Lemmy in general?
On the web interface, go to your account settings and out of all the languages selected; ensure that "undefined" is one of them. You can select multiple languages by holding down the "control" key and clicking. For example, right now I have both "english" and "undefined" as the languages I use.
My settings page looks like this. So are you saying that this Languages box should have a list of many languages, including "Undetermined"? Right now there is only English and nothing else.
Can I add more languages or is that instance admin level?
Oh, yeah I guess that would be an instance admin thing cause mine has a whole bunch in that settings box. Let them know that "undetermined" needs to be included as an selectable language.