Most “core” filetype features are covered by autocommands, so disabling them will have the effect that you want. But we only want to disable them when opening a particular file, so :noautocmd edit {file} I’ll update with more information on the autocommands and features when I get to my laptop.


Interesting situation. Let's first address debugging it. It seems your experience with adding a normal iABCDE to the .vim/ftplugin/mail.vim and seeing it twice really suggests this file is being sourced more than once. I think one thing you can try is adding statements that can display where &filetype was set and also show the stack trace of the function ...


When in doubt look into the standard Vim runtime files. ts sts et sw should be set by after/ftplugin. sta is basically no-op, as you have &sw == &sts anyway. si ai are basically no-op as you have &cindent on. And also, in general, there's nothing in setting ai si on if you have any meaningful indent/xyz.vim. cino should probably be set by after/...

Only top voted, non community-wiki answers of a minimum length are eligible