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Both In-Reply-To and Referenceswhen enabled will drive Original Issue Key and Message ID association based on the header related to the enabled check boxes.

Old view

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New view

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Behaviour Changes

1. If both In-Reply-To and Referencesheader options are enabled then In-Reply-To option will take precedence.

2. Message ID Embedded Issue Key will now take precedence over Original Issue Key and Message ID association

3. If both options are disabled then previously we would depend on the main checkbox Email Threadingcheckbox however this property has been removed. Now the options: Use References Header checkboxandUse In-Reply-To Headercheckbox will drive Email Threading.

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If you have previously only enabled the Email Threading and none of the sub options Use References Header checkboxand Use In-Reply-To Headercheckbox then you may be affectedboth options will be enabled.

What do I need to do?

Due to the removal of the Email Threading option and used this to drive email threading There are no changes required on your end as this will be automated. If you do not wish for both options to be enabled, you will need to enable the appropriate header option. If you wish to achieve the same as previous behaviour then enabled both the Use References Header checkboxand Use In-Reply-To Header checkboxmanually change and disable the association headers you do not wish to use.

Further information on the Email Threading for issue association can be found here: https://thepluginpeople.atlassian.net/wiki/spaces/JEMHC/pages/72908873/Understand+how+Issue+association+works#Email-threading