[yamaneko]

Mine only worked when I added [this][1]:

    set t_ZH=^[[3m
    set t_ZR=^[[23m

before `highlight Comment cterm=italic`.

I was recently wondering how I'd make some keywords italic, like VSCode, which italicizes `self.foo` and others in Python. This thread came at the right time. I found this [post][2] that may help, in combination with OP.

[1]: https://stackoverflow.com/a/21077380/

[2]: https://www.reddit.com/r/vim/comments/dgbvw4/how_can_i_have_...