I think the error in your case also proves the misbehavior of forward-comment, and it breaks `uncomment-region' in my case. And with the suggested fix applied, and then recompile/evaluate, `uncomment-region' works as expected.
Yang: Have you loaded/compiled/provided the toml typescript-grammar before using this mode?
The *-ts-modes depends on external grammar in order to properly initialize the major-mode and provide correct highlighting and indentation.
I only have the required shared libraries (libtree-sitter.so & libtree-sitter-toml.so) installed. This should be enough, right? At least `treesit-explore-mode' works fine in toml buffer.
Regards,
-- *Yang Yingchao*