We are now nearly 200 (!!!!) patches behind mainline Vim. There hasn't been a patchlevel update in nigh six months.
Is
github.com/b4winckler/macvim abandoned? I sincerely hope not.
I don't know the relevant languages, or about MacVim-specific internals, or
else I'd try to bring the Vim patchlevel up to date myself and make a pull request. I'd be afraid to accidentally clobber something MacVim-specific.
Charles