I am running Opera 12.16 x64 on Win-7 x64 - Intel I5 - 8GB RAM. I have installed Opera_Next_19.0.1326.21 (x32) side-by-side. (See my post elsewhere).

Almost all the gmail problems are gone. Do not have a scroll bar for my contacts/labels, but I can scroll over it for the time being. Gmail is finally working as it should. Some images do not display - although settings are set to display all images... Some sites may still have a problem with pictures/graphics, etc..