No notification when creating a label which already exists
Related to: #26945 (closed)
When a user tried to create a label which already existed on the new/edit issue page. There was no notification to inform him that the label already existed, therefore it wasn’t clear to him what was happening. [Clip 1] (https://youtu.be/UF_zfCYgukw?t=11m22s).
I think we need a message here to let the user know that the label already exists.