I’ve been receiving asks from people (and seeing posts under the XKit tag) saying that after installing XKit, they started seeing ads on Tumblr. I would like to make one thing clear: there is absolutely not a single line of code in XKit that would cause ads to appear.
I loathe ads as much as the next guy and would rather make XKit a paid product than display ads on your dashboard. (Edit: Tumblr do display ads on your dashboard as “sponsored posts” and on search pages, those are unrelated to any software you might have installed.)
If you are seeing ads on top of the page, getting popups, etc, I recommend installing a security application and performing a check (make sure it’s not rogue, though) and then go through the list of installed extensions to make sure you do not have an extension that you don’t remember installing.