Hard hangs while typing after resume from suspend

I’ve run Fedora KDE spin on a Thinkpad T460 laptop (8GB, Intel® Core™ i5-6300U, Intel HD Graphics 520) with external monitor and Logitech wireless USB mouse for 7 years, the last few atop Wayland. In that time suspend has worked reasonably well; sometimes the laptop comes out of suspend “on its own” within minutes of entering suspend (web search suggests this might be a USB issue).

But for a few weeks now, I resume after choosing Sleep in KDE, and soon in the middle of typing the system hangs. No cursor motion, keyboard unresponsive, lid close does nothing; if the fan was on it stays on. I can only do a hard power-off. Upon powering on, there is no journald information about the hang, typically no journald entries from around the hang, and then lots of boot logging with no obvious smoking gun. One non-standard thing about my setup is I mount an NTFS partition read-write with documents and Firefox and Thunderbird app data (not kernel, not root, not home directories) using the ntfs-3g userspace driver; maybe that FUSE driver hangs hard, maybe when KDE’s baloo indexer reindexes some file on NTFS? But this is pure conjecture, and doesn’t explain why it never hangs until after I suspend then resume.

I always and mostly run konsole, Firefox and Thunderbird for Wayland, and KeePassXC. The hang has occurred while typing in the terminal, typing in Firefox, and once just typing my password at the lock screen. It’s usually within a few minutes of resuming. I don’t think it’s hung while just browsing and scrolling. It doesn’t seem a hardware problem since I’ve never had a hang after power-on, only after resume from suspend.

Any suggestions in how to debug this? I can’t find a Fedora guide to debugging suspend-resume. Is Ubuntu’s guide appropriate? It suggests enabling /sys/power/pm_trace. Others suggest disabling the kernel i915 Intel graphics driver. The wrinkle here is that suspend and resume both seem to work, but shortly after resume I reliably experience the hard hang. So maybe I need to consult a “debugging input hangs” guide. Thanks! :hugs: