As WordPress user, I tend to install to various plugins. A lot of plugins. And after that I also tend to uninstall most of them, saying “aha it seems it does this” or “huh it doesn’t do what I want” or “meh it doesn’t do the way I want”.
At this point another aspect for plugins appears. Clean uninstall. What i mean is leaving the site and database of the site as it enters. But it turns out some of them or many of them fails at this point.
When I press “remove” link and see that it disappear, I think it is removed. But when I look at the MySQL and see the leftovers of that plugin in various tables I reach and epiphany that my thought is misguided.
I don’t remember if it was something I said or that was own personality of that blugin but it seems this one was a messy breakup.
So as a piece of advice, remove doesn’t mean that that plugin is removed. You might want to check the table as well.