UPDATE: Resolved
Turns out a server restart is required to get the onBlockBreak event to work in a custom trigger.
All is well.

== original message ==
I'm unable to get the onBlockBreak event to trigger.

checkBlockBreak.yml:
Sync: true (or false, tried both) Event: onBlockBreak <-- also tried org.bukkit.event.block.BlockBreakEvent, no success
checkBlockBreak.trg:
#MESSAGE "Broke a block"

Result: no response from trigger when breaking blocks as deopped regular player, or any type player