For some odd reason, Firefox 35 will suddenly display a black screen. I tend to open two browsers and within those browsers open up two or three tabs. I often minimize one browser to use another and then minimize the current browser to maximize the previously minimized one so that I can use it. This has worked fine with other versions but for version 35 it causes problems. Black screens display almost daily and it's becoming a big hassle. I've had to use IE much more than I like (IE has a lot of problems with viruses and trojans) but the problems with Firefox leave me little choice. What is causing this problem? I also get messages saying that I'm using a lot of memory on Firefox - even after I've only been using th browser for a few short minutes. I do have a lot of websites bookmarked but these have been accumulating through various versions of Firefox so I don't know if that's the problem. What can be done to fix this problem?