I can remove a tag that is assigned to a photo from the right hand side too.
maybe i'm not explaining it correctly ....
open a new (untagged) photo in the viewer, click the 'add tag' button. i get
a long list drop down of old tags, i want to clear that drop down list.
> i have full page viewer open and have just right clicked on one of the
> tags in the right hand preview pane and selected remove tag and it
> surely did...I'm sorry that it is not working for you but I have no idea
> what may be stopping you doing the same as me.