Vim has this awful annoying habit of splitting my commit messages and automatically line-breaking them, rendering the second line with a red background for some reason.

How can I make vim stop doing this?
I found the setting I needed in ~/.vim/after/ftplugin/gitcommit.vim was:
setlocal textwidth=0
The filetype plugin enforces the preferred Git commit message style: Short title, and hard line breaks. If you don't agree with that style, undo the settings by putting the following into ~/.vim/after/ftplugin/gitcommit.vim:
setlocal wrap formatoptions<
formatoptions< could be a valid argument to setlocal, the docs for :setlocal explain that it will “Set the local value of {option} to its global value by copying the value.” So this command will remove the t and l flags (documented in fo-table) that the plugin adds to 'formatoptions'.
twandwmset to? If they're set to non-zero values, you will get automatic line breaks inserted (by default at column 80).gitcommit.vimsyntax highlighting module and the guidelines were written by Tim Pope. You can read them here: tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html. For a quick summary, make the first line a 50 character summary, leave a blank line, and then write your paragraphs below.gqto fix the line breaks.gqiptogqtheparagraph you'rein.