git remote add upstream https://github.com/symfony/symfony-docs.git
Edit .git/config
In upstream block add fetch = +refs/pull/*/head:refs/remotes/upstream/pr/*
git fetch upstream
git merge upstream/pr/5285
git remote add upstream https://github.com/symfony/symfony-docs.git
Edit .git/config
In upstream block add fetch = +refs/pull/*/head:refs/remotes/upstream/pr/*
git fetch upstream
git merge upstream/pr/5285