I wonder if you have asked and obtained answers for how many tabs can be kept open on IE & Chrome? I think we may actually collect metrics on the number of open tabs, and I know it has been discussed in the past but I do not recall exactly where. I would hazard a guess at saying that most people would have under 100 tabs open few would attempt to keep over 300 open and over 1000 is probably almost unheard of. To some extent it will depend on the content of those tabs. If for instance they are streaming HD video, or are large databases of webmail they will be more resource hungry than a short webpage containing only a couple of static images. It will also be affected by the platform and machine used. A use case for needing or having 10,000 tabs open and trying to manage and view the tabs is rather hard to imagine. Remember we have bookmarks and multiple complex ways to manage those. I am sure keeping large numbers of bookmarks makes more sense in most use cases than keeping large numbers of open tabs. The numbers of bookmarks is I believe to some extent set according to the computers specification and includes a trade off with the amount of History that is stored. Also the number of open tabs doesn't just affect whether or not Firefox crashes but also the speed of opening, and the ease of navigation amongst those tabs and or Windows. Thinking about your own situation as you are apparently posting from a 32 bit XP you may find it less capable than newer machines and will not be able to upgrade to a 64bit Firefox.