When I open the settings.json file and go to the line that I need to change,
I see a pencil left to the line, and the line gets highlighted when I click on the pencil, all of this heavily suggests editing :
But it turns out I cannot edit the line. Anything I type has no effect whatsoever
on the line and the settings.json file remains unchanged.
I also tried the other settings.json file next to it, but I get an error message
as follows :
But I don’t think you need this configuration. I have tested with a simple file in a clean editor with only this extension installed and it seems to be detected correctly. You can check the language mode at the bottom right of your editor, next to the little smiley face, it writes which language mode is currently active. And you can change it by clicking on it.