https://connect.mozilla.org/t5/discussions/cpu-hogging/m-p/134751#M54263 <P><a href="https://connect.mozilla.org/t5/user/viewprofilepage/user-id/136255">@DarkSky</a>&nbsp;</P><P><A href="https://bugzilla.mozilla.org/enter_bug.cgi" target="_blank">https://bugzilla.mozilla.org/enter_bug.cgi</A>&nbsp;&nbsp;</P> Fri, 14 Aug 2026 12:56:07 GMT igorlogius 2026-08-14T12:56:07Z https://connect.mozilla.org/t5/discussions/cpu-hogging/m-p/134735#M54254 <P>I often have about 30 or 40 tabs, waiting for attention.&nbsp; My Win-11 UI was borderline unresponsive, Zen needed as many as five seconds to pause a YouTube post, clicking on the pause button was a little more responsive, but still a couple of seconds from click to action.&nbsp; My cursor disappeared over the Zen window, ... (meaning Zen was very busy doing other stuff) even though I still had about half of CPU available (on a 16 'thread' Core-i9 processor) with 128GB of RAM.&nbsp; Closing Zen and restarting (reloading all of the previous tabs) got the CPU utilization down to 11%, so I suspect there were zombie threads dragging the machine down.&nbsp; I think that deserves investigation.</P> Fri, 14 Aug 2026 07:27:05 GMT https://connect.mozilla.org/t5/discussions/cpu-hogging/m-p/134735#M54254 DarkSky 2026-08-14T07:27:05Z https://connect.mozilla.org/t5/discussions/cpu-hogging/m-p/134751#M54263 <P><a href="https://connect.mozilla.org/t5/user/viewprofilepage/user-id/136255">@DarkSky</a>&nbsp;</P><P><A href="https://bugzilla.mozilla.org/enter_bug.cgi" target="_blank">https://bugzilla.mozilla.org/enter_bug.cgi</A>&nbsp;&nbsp;</P> Fri, 14 Aug 2026 12:56:07 GMT https://connect.mozilla.org/t5/discussions/cpu-hogging/m-p/134751#M54263 igorlogius 2026-08-14T12:56:07Z