Firefox locks up after downloading file
Firefox runs fine most of the time. If I right-click to download an image, or click a link to download a PDF or other file, or Save HTML, I see the "Save file" dialog, cl… (read more)
Firefox runs fine most of the time. If I right-click to download an image, or click a link to download a PDF or other file, or Save HTML, I see the "Save file" dialog, click Save and then Firefox freezes up for a while, maybe a minute or two. Pages won't scroll. I can't switch tabs. I can bring up a different firefox window and it redraws its contents, but I can't scroll or do anything else.
This didn't happen a month ago, then one day after a system upgrade, it happens every time. I'm using FF 123.0.1 on Arch Linux. 64GB RAM, so it's not a memory shortage. I have upgraded one or two times more since the upgrade when this appeared. Chromium is not affected, Thunderbird is fine, and all other software continues to be fine as before, including when saving files. Only FF has this problem.
What is the problem and solution? Are there ways to gather more info to diagnose the problem, if needed?