Typing in "Add Tag to 1 Item" and click away deletes the entry

If you’re typing in “Add Tag to 1 Item” and you, for example, click in "Add our notes here…, the entry in tag goes away. Should either leave the tag partially completed or ask what you want to do.

Nit: Should be “Add Tag to One Item” or “Add Tag to Item,” but I’m not sure I understand the need for one, probably if multiple photos

If you select more than one item, the metadata panel is in ‘bulk editing’ mode: i.e., you’re modifying multiple items at once. That’s the reason for ‘Add Tag to One Item’ vs ‘Add Tag to X Items’.