Issue Summary

The Date Picker field type does not respect the date format configured in ⚙ > System > General Configuration > Advanced Settings > jira.date.picker.java.format (nor in ⚙ > System > Look and feel > Day/Month/Year Format)

Whenever this field is edited in a Jira issue, the date format is always using the format 13/Aug/24. As result, when trying to submit the new date value, the error below is thrown

Invalid date format. Please enter the date in the format XXXXXXX

Environment

This issue was observed in Jira Data Center 9.12.12, but we suspect that any Jira 9.x version might be impacted.

Steps to replicate

1. ⚙ > System > General Configuration > Advanced Settings
   • Set jira.date.picker.java.format to yyyy-MM-dd
     
2. Create a new date picker field in ⚙ > Issues > Custom Fields
3. Edit any Jira issue
4. In the Edit Issue screen, scroll down to the date field, choose a date and click "confirm" from the calendar
   
5. Click on the Update button from the Edit Issue screen to submit the update

Expected behavior

• After clicking the "confirm" from the calendar, the date format should respect the format configured in the Jira administration which is yyyy-MM-dd
• No error should be thrown after clicking the Update button

Observed behavior

• After clicking the "confirm" from the calendar, the date format should respect the format configured in the Jira administration. Instead, it is using the format below:

  13/Aug/24
  

• The error below is thrown after submitting the update:

  Invalid date format. Please enter the date in the format "yyyy-MM-dd".
  

Workaround

Workaround 1

Revert the change made to ⚙ > System > General Configuration > Advanced Settings > jira.date.picker.java.format to use the default format

Workaround 2

Manually enter the date in the Date Picker field in the Edit Issue screen, using the format configured in jira.date.picker.java.format: