Is it possible to develop a GUI that let's you easily delete a tag permanently?
I have misspelled a tag and now it keeps comming as a suggestion. It's pretty annoying.
It would really be helpful to be able to delete this tag from the list of used tags
In order to make sure that the tag can't be deleted accidentally Joplin should check if the tag isn't assigned to a note.
Thanks!
On Joplin desktop, just add the mispelt tag to a note, then on the tag list down the side, either rename that tag or delete it
EDIT: Actually you can delete or rename tags on mobile too, if you long press a tag in the tag list
Ok thank you a lot, it worked, I'm happy! 
One addition in order to help others to avoid the troubles I had: "the list down the side" means on the left where your created notebooks are, when you scroll down you'll find your created tags. There you can delete them or rename them with a right mouse click.