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If you have an enterprise subscription, advise your technical account manager or support contact at Magnolia, to make sure we assign a Magnolia staff member for review. They will make sure our maintenance team is informed and coordinates the review with Magnolia staff.
If you are a community user, please create a ticket in Jira describing your fix or improvement. Please also drop us a line on the Magnolia Developers Mailing List 
. Mind that we groom community tickets in Jira once a week.
You will be required to sign the Magnolia Contributor License Agreement.
Once assigned, Magnolia developers will help you as best as possible to discuss the changes, as well as to pass various validation steps (e.g. code style, tests, PR builds).
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