Your IT Department is absolutely, undeniably, wrong.
If something is not listed on the "Supported Platforms" page for your version, then it is not supported. OpenJDK is clearly not listed on https://confluence.atlassian.com/adminjiraserver073/supported-platforms-861253018.html therefore it is not supported.
I can also tell you that it doesn't work - Jira will start and run, but throw certain errors and gradually fail (more and faster if certain add-ons are installed)
@Jack Graves [AC] first caught our eye with his incredible breakdown of what, in his opinion, can make or break a Jira software implementation. (Read his thoughts on this thread)! In this follow...
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