Make it like Opera 12.16 or earlier
I was using an excellent Opera browser until version 12.16. I used it from the very first released version to 12.16. I still use that one. The reason is that there was an absolutely great capability to have multiple open windows within Opera window. It is just incredible feature for people who do a lot of Web searching. For unclear to me reasons, none of the other browsers have this capability. Yes, they can give you multiple independent open windows or tabs, but I want them to be organized with one browser window. This was the major reason I used Opera during all this time and I miss it in the other browsers.