User blog comment:DaNASCAT/Technical Update: September 18, 2017/@comment-126761-20170919141750/@comment-126761-20170919155220

Could you send examples in to Special:Contact/bug? The styling was updated in this release, but only as part of a general Tabber code upgrade - we can look at making tweaks to it if needed. Thanks!

Edit: it looks like the WARFRAME Wiki tabber overlap issue is down to a bit of custom CSS there (I've supplied details in my Special:Contact reply).