Reproducer:
unit=run-json-trigger-$(date +%s)
sudo systemd-run --json=short --unit="$unit" \
--on-active=30s \
/bin/true
Before, trigger mode accepted --json=short but printed only human-readable
"Running timer as unit" and "Will run service" lines. Reject the option
until trigger mode has structured output.
Follow-up for fe5a6c47af