Weird tab behavior in Google Chrome

I run Chrome as my primary browser (so far) and it has never failed me. Yesterday however, I began to see a very strange behavior. As soon as I would click on any tab (other than the first tab), Chrome would start cycling down through the tabs. I.e., if I clicked on the 4th one, it would switch to that, then to the 3rd, then the 2nd, and finally the first tab (where it would remain.)

Switching to a new window (with only one tab) would work fine but as soon as another tab was opened, the same behavior.

Survived through reboots, chrome upgrades etc.

I think I have isolated this to either a funky (dirty?) keyboard or flakey mouse. Once I disconnected both the external keyboard and mouse, things returned to normal. Now doing the bisect to see if mouse or keyboard. One note: My kitchen has been under renovation for the last month. Consequently, I've done a lot more "eating over the keyboard" than normal, so maybe I just dropped some weird crumb that effectively doees control-pageup repeatedly (or some other previous tab command over and over.) I didn't notice this behavior in other "tab oriented" programs (such as gnome terminal or Firefox.)

Updates here if I further resolve this.

Oh and some search terms in case anyone else runs into this:
ubuntu
chrome
chrome-beta
(occurred in both)
tab switching
autotab switching
tab bug
google chrome tab bug
google chrome tab autoswitching bug

(Oh and for those playing along at home: restarted chrome numerous times, disabled all extensions, rebooted, upgraded Chrome, upgraded all Ubuntu packages--basically did all the "best practices" I could think of to work around this. The only work around seems to be disconnecting mouse and keyboard (which were plugged into a USB C dongle providing legacy USB connections.) System is HP Spectre x360 15" touch with 8th gen i7 running Ubuntu 18.04.2

Mouse seems to be working fine.

Blew some dust/gunk/ick out of my keyboard and now everything seems to be working again. (The peripherals are attached in the same order, same location.) So LIKELY the keyboard? The world may never know (and I'm sure the world will never care.)