When I put a tag on a post, Tumblr saves that tag. Meaning, when I start making a tag on a different post later, it lists suggestions for autofill from previous tags I’ve made which so far have all been saved. How do I make Tumblr stop doing this? I want to delete some of the tags which I think are already useless.
For the tab suggestions you'll have to go back to previous posts and remove them manually. Once that's done you'll be able to get the autosuggestions to stop.
One way to check is to go to
yourtumblr.tumblr.com/tags/tagiwanttodelete and make sure none are there.
However, popular tags used by other Tumblrs will still show up in the suggestions.
If you have the Tumblr app, type down the search you want and look on the top right corner of the screen. You'll see a setting button or one like that, click it and change Save this search so that it will not be a saved tag.
Type in the Tag you want to delete. When it pops up, click it, then hit untrack.
If you have the app just click on the tracked tag and it will either say track or tracking and if you click on that so it says track it will not be on your list of tracked tags. I don't know if this works on a computer or not hope this helped!