Doesn't occur in 2.5.7.
Does occur in 3.0.0-quality-assurance-alpha-7
1. Mounted a known MongoDB with mount point of d1
2. Clicked move/rename icon to rename it. Gave it a name of d2 and clicked Rename
3. Still shows up as d1 instead of d2, but now shows up as a directory.
4. Deleting d1, which one might think is just a mount, results in all databases being deleted from Mongo.