Zotero 5 : Ghost tags
I haven't been able to find this anywhere in the forum. I'm using 5.0.25-beta on Ubuntu 16.04 LTS. I find that when I delete tags from an item that it does not disassociate the item from the tag. If I select the tag, the (now untagged) item will be selected and display in the main pane. The item is greyed slightly, and the still-tagged items are dark black. This isn't a big deal (partly because I hardly use tags) but if it's affecting others it be confusing.