I've experienced this on many of the different Bimmerpost forums that I frequent. I use either Chrome or Firefox and have the same issue. Not sure why, because I don't have this problem on other forums that are running vBulletin.
Mine: 2016 M4 | Sakhir Orange | Black Full Merino | CF Trim | M DCT | More | ED 5/13/16
Hers: 2011 335is Coupe | Le Mans Blue | Black Dakota Leather | Dark Glacier Aluminum | 6MT | ED 5/12/11
Also Mine: 2006 Z4 Roadster | Interlagos Blue | Black Extended Nappa Leather | Carbon Leather Trim | Purchased 7/19/12