Git “error: The branch 'x' is not fully merged”

Question

Here are the commands I used from the master branch

git branch experiment
git checkout experiment

Then I made some changes to my files, commi

Answer 1

I had this happen to me today, as I was merging my very first feature branch back into master. As some said in a thread elsewhere on SO, the trick was switching back to master before trying to delete the branch. Once in back in master, git was happy to delete the branch without any warnings.