One of my team mates created a branch that included a pound sign: feature/example-#123. The pound sign appeared to prevent the branch from showing up in the GitUI window under both the short list of local branches and the expanded list when you click "More..."
Fortunately, he was able to "recover" his work through Embedded git by switching into Expert mode and creating a new branch without a pound sign in the name.
Version: 2.14.0