Character literal such as
#\[ (equivalent to
'[' on other language) disturbs syntax highlighting for matching parentheses.
As Scheme uses a lot of parentheses, it is very hard to trace parentheses if syntax highlighting is broken.
This syntax highlighting comes from here. I imagine the bug is in this file. It seems that that repo doesn’t accept Issues but does accept PRs.
This isn’t something the Exercism team will fix, but if anyone from the community wants to fix and PR over there, we’d gratefully update our dependency.