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I don't think that's it. This has been going on for at least 1 year now. It seems as if Firefox has some rogue processes that it is not stopping or cleaning up properly. There's no way the downloads screen by itself should consume that much RAM.

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But I don't have any open websites! This should only be relevant if Firefox is failing to close websites properly when the user closes websites. I expect Firefox to stop processes associated with a website and deallocate memory when a website is closed. Otherwise they are just inviting problems to occur.

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Why? I don't care what the process count is, just that Firefox is consuming 1.8 GB RAM with ZERO open websites.

I am also battling with a RAM issue. You may find something useful in the following article. https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-or-cpu-resources

Thank you! I did find that page a while back. Restarting Firefox will solve the 1.8 GB memory problem temporarily. Unfortunately it comes back the next time I use the browser. Yesterday Firefox locked up my computer so badly I had to just pull the cord, which causes me great distress. Then today in reviewing the forum I see many unresolved user complaints about memory leaks in the last year or two, so it seems to be a common problem. Then I found details on Firefox's declining market share and it pretty much completes the picture of what is going on. I stuck with Netscape for a long time and the same with Firefox, but it is time to move on.