Hi T, kk, et al
Just a few minutes ago, working on PDF documents, Prefs, Keyb, Shorcuts, Apps stopped working for an App. Check the entire system, no such shortcut provisions excepting mine truly.
Regardless, reset my shortcuts to something else, and they all started working again. Point is, Mojave has proved to be sloppy hanging onto user shortcuts for 3rd party, a few times here. ST being 3rd party, you might want to check out quick-and-easy reassignment that worked here.
For ST Mac'ers, further. Just before my shortcuts for 3rd party failed, 10.14.3 update notification. Would not be the first time OS preoccupation with security got sticky. Exploring Text Expansion", you might want to keep in mind that many systems and manydevices and many app-os interactions determine suitability of purpose. Suitability, being where T seems to be lingering.