Tested in 8.1.25, 8.1.48, 8.3.2
To reproduce, structure;
Root
-Folder 1
–Tag 1
Select tag 1, press Ctrl C, Ctrl V, Tag 2 will appear in folder 1. However, immediately pressing Ctrl V again will result in a tag called “Tag 1” being placed in the root tree, and the whole tree of folders will also collapse.