Alert Notification Email Subject Modification

I am using Graylog 3 and alert notification emails.
We receive alert notification emails without any problem.
But some time we get lots of email from graylog and it is very hard to see which facility or caller has error.
I want to show caller/facility or any other meaningful field in subject line of emails.
I use backlog messages and I know we have to iterate its in for each block.
Is possible to write any field in the subject line like that {firstmessage.fields.logCaller()} or
LoggerName: ${firstmessage.fields.LoggerName}

currently with the default Graylog mail notifications only the documented changes are possible:

Your requested is not possible with the provided notification plugin.

Thank you for your comments.

Can you suggest a free plugin or any other solution?
I have tried opsgenie but free plan does not permit message customation operations.
My other problem about aler scheduling. I dont want to get alerts in quiet hours(weekends or after midnight until morning hours). Do you have any suggestions?

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.