Having separate processes for each tab will increase resource usage. This isn't a problem if you've got a standard up-to-date home computer, but is a problem for someone with outdated hardware like me. The thing is, there currently is no other browser that matches what Firefox can do for me in terms of plugins and tab management (particularly the ability not to load all tabs on start-up, but only the one I was looking at, which is helpful for saving RAM and bandwidth). If Firefox moves in a way that increases its resource usage, what alternative will there be for me? I will refuse to use an old version, and will be just left behind.

Note that I am welcome for suggestions of browsers that can potentially be a Firefox replacement if Firefox ever is no longer usable due to high requirements.