After updating both my Mac and iPhone to the latest OS 26 versions, Continuity/Handoff wasn’t working anymore, meaning no more cross-device copy-n-paste etc. Rebooting either device didn’t change anything.
15 mins of searching brought me to a Reddit post by /u/shesabadone which suggested resetting macOS' useractivityd:
defaults delete com.apple.coreservices.useractivityd
killall useractivityd
It did the trick!
