Until some minutes ago, I had Opera 38.0.2220.41 and the issue was present. With Chrome, Firefox, Internet Explorer, Vivaldi, SRWareIron and Maxthon, the controls disappear in 1-3 seconds.
I just updated to 39.0.2256.43 and the controls disappear, so the issue seems to be solved. Also now the controls look different, so it seems they did change something there. All this on Windows 7 x64, by the way.