Created by: Herst
https://github.com/twbs/bootlint/wiki/W007
Found as part of my work on bootlint for BS4: twbs/bootlint#410.
I created the following one-liner to do it:
find docs/ -type f -exec perl -pi -e \
's/(?<=<button )(.*?)(?=>)/@{[(index($1,"type=")!=-1?"$1":"type=\"button\" $1")]}/g' {} +
BTW, I am occasionally rebasing my patch branches so you shouldn't need to merge the current HEAD of v4-dev
into my patch.