Firefox performance problems are usually opaque to me. I always have too many tabs open. I don't like any alternatives that I've found. Bookmarks have only gotten worse. I can tell that Firefox is eating too much CPU when my computer's fan comes on (all performance problems on my desktop seem to be Firefox related). Finding the bad tab(s) isn't always easy. You can try to analyze what's going on with the URL <about:performance> It tells you the memory and CPU resource usage for each tab, except some things don't get assigned to tabs. That display seems to have gotten less useful over time. What prompted this message is yet another time this happened. I found that the bad tab was: <https://arstechnica.com/information-technology/2024/10/finally-upgrading-from-isc-dhcp-server-to-isc-kea-for-my-homelab/> This is a topic that I want to study. Later. I had had it open for more than a week. This tab was burning more than one core's worth of CPU. I deleted the tab. The fan became silent. Then I re-opened it and the load was much smaller. That's today's ad hoc solution. Quite unsatisfactory. Does anyone else have a recommendation for investigating and fixing some Firefox performance problems?