I've been trying out the feature/pgtk branch for a while, and I've run into a mysterious shutdown (not crash) that I haven't been able to isolate yet. I'm wondering if anyone else is seeing something similar, so I can gather enough data to file a big report.

I'm running emacs in daemon mode, with at least 2 frames. The shutdown happens in eww buffers, when I'm scrolling, and perhaps always (at least a couple times) when I'm scrolling up with M-v. Perhaps relevant, I often use eww to make web pages more readable, and this often involves me making the buffer writable (C-x C-q) and removing (killing, ala C-k and C-w) extraneous junk, which includes images and styled text in various sizes and perhaps fonts.

This isn't reliable enough for me to catch it under gdb, but I'm trying. Has anyone else seen anything like this, or perhaps the above behavior description is enough to suggest something I might do to tickle the issue? 

Thanks in advance,
~Chad

P.S. My environment is pretty weird; I'm running emacs inside Crostini, a debian container running on a lightweight vm inside ChromeOS. This system uses a wayland-based display engine with a chromeos-custom compositor with X11 support, described in some detail here: https://chromium.googlesource.com/chromiumos/platform2/+/413a646b5b7067a989bab2ef9fca0c3a4515cc22/vm_tools/sommelier/README.md