JSON log filter plugin is not installed by default and it seems it cannot be installed through the Rundeck GUI. To install it manually enter the container

 docker exec -it rundeck-docker sh

Enter the libext directory and download the jar file:

cd libext/
wget https://github.com/rundeck-plugins/jq-json-logfilter/releases/download/1.0.4/jq-json-logfilter-1.0.4.jar

You should now have the log filter in the Workflow under Global log filters

• Dockerized rundeck 4.5.0
• Host rundeck installation in /var/lib/rundeck

• https://github.com/rundeck-plugins/jq-json-logfilter