auto-complete for parent field does not work well.

Issue Summary

When searching for issues in the Parent field on the create and edit issue screens in JIRA, the searching with partial word does not show the list well.

This issue is particularly problematic for Japanese users, creating a significantly poor user experience, where even entering the complete name of an Epic sometimes yields no results.

Similar behavior was found a few years ago when the UI was using the old issue view. Reported under bug https://jira.atlassian.com/browse/JSWCLOUD-19247 now replicated in the new issue view.

Steps to Reproduce

1. create an epic with long name
2. search the name of the epic on the parent field with partial match

Expected Results

auto complete works well

Actual Results

some of partial match does not show any result. 

Workaround

At the moment, the only available workarounds are to select the Epic without using the search function, or to keep searching with a partial word until it eventually appears in the Parent field.