When trigger is created from trigger prototype its recovery expression is not valid:
SNMP example(only first part of recovery expression before OR is not valid):
Trigger from prototype
To reproduce SNMP example: import buggy template , assign it to some snmp host and check the results.
To reproduce Linux example: edit default OS Linux Template(Filesystem discovery trigger prototype as on screens: add recovery expression with different value)
Note that in SNMP example on first part of recovery (before or) is not valid, and in Linux example both parts of the recovery expression are not valid.