Disabling spell check in certain cases

[xsrvmy]

It looks like vimtex already turns off spellcheck for commands and inside math mode. Is it possible to also turn off spellcheck

1. Inside a magic comment (eg. %!TEX root=main.tex marks 'tex' as misspelled, but I don't want to add that to the dictionary because it's a common typo for text)
2. For words that follow math immediately without a space (specifically things like $n$th)
3. In commented out code

[lervag]

1. Inside a magic comment (eg. %!TEX root=main.tex marks 'tex' as misspelled, but I don't want to add that to the dictionary because it's a common typo for text)

Agreed.

2. For words that follow math immediately without a space (specifically things like $n$th)

I've tried to fix this and I think it should work. Please test.

3. In commented out code

This is already supported with let g:vimtex_syntax_nospell_comments = 1.