I was editing this question to add some tags, then entering the edit reason I used autofill as seen in the screengrabs. notice the difference between the autofill suggestion and what actually appears in the box, "tags added" becomes "tags added added", while "tags, capitalisation, make it a question" becomes "tags, capitalisation, make it a question, capitalisation, make it a question". So the autofilled text is getting added twice, but it also seemed weirder at one point, didn't get a screengrab of that particular one.
I'm on Safari/Mac
Is it a bug? Can it be fixed?
Added info: the duplication happens when I click on the items in the dropdown list visible. When the text autofills by itself the first time, it works fine (if that makes sense) but then when I click around on the choices then the duplication happens.