Is this possible by including the correct scope in the grammars list to use Atom's spell check? I'm not sure what the right grammar for a ftml file would be, though.
I don't think this is possible. FoldingText for Atom doesn't use the standard Atom text buffer, it's build using a custom HTML/DOM view, so can't reuse any of that functionality.
Is this possible by including the correct scope in the grammars list to use Atom's spell check? I'm not sure what the right grammar for a ftml file would be, though.