I've been having an odd problem. My laptop works like a charm on its own. However, when it's connected to a USB-C dock and screen, suddenly apps that were working great start eating up lots of CPU. (Such as Firefox, Thunderbird, and Zoom.) After a bit of debugging, I realized that the issue isn't even whether I'm connected to the dock, but rather whether the laptop lid is open or closed: close the lid and all those apps eat up CPU; open the lid and CPU drops and everything is groovy. I can't for the life of me figure out what's causing this, and my searching hasn't been able to turn up a clear cause or solution. Would anyone happen to have experienced the same issue, or be able to point me in the right direction as to the cause? I'm running XFCE, with the display settings set to "mirror displays" (i.e., the internal laptop screen and the external HDMI monitor). Thanks, DR