One of the best things about ad blockers is that they are really just general purpose content blockers. Want to disable this permanently? Here's an Adblock Plus-compatible filter to block the div if you find it annoying. Tested and working on uBlock Origin:
! Disable link preview popups on Wikipedia
en.wikipedia.org##.mwe-popups
It's just a div with the class ".mwe-popups", and using your ad blocker will persist the change after clearing cookies, which the preference setting (mentioned elsewhere here) does not.
For Wikipedia in different languages, just change the subdomain in the filter.
For Wikipedia in different languages, just change the subdomain in the filter.