I have a problem only with c and cpp questions in code runner. There is no syntax highlighting only for them. I made a test for Pascal, Java, Python and everything is OK.
I also try to use code snippet suggestion for some keyword with CTRL + space, but that also doesn't work. If I put cursor on white space and hit CTRL + space it only suggest previously declared variables in the written code (img1).
I don't think the problem is in the theme I use for Moodle, because the problem mentioned doesn't occur in other programming languages. I will attach some pictures.
Tested also on production site with same problem.
The program compiles without any background issues and provides answers about which test cases it meets and which doesn't.
Second image is inspect element of page where c-question is loaded.
Thanks in advance.
Moodle 3.4.9 (Build: 20190513)