After JSM upgrade Insight custom fields values are empty

Issue Summary

• After JSM upgrade to latest 4.13.X or 5.0 version Insight custom fields values into issues looks empty while in Insight those objects still show the right connected Jira issues.

This is reproducible on Data Center: yes

Steps to Reproduce

1. upgrade JSM to latest 4.2.X or 5.0
2. reindex Jira
3. reindex Insight

Expected Results

Insight custom fields values should remain untouched after Jira upgrade.

Actual Results

Insight custom fields values are cleared up over Jira issues.

• customfield description/name is still on the issue (which should not be the case when values are cleared)
• By looking at affected tables in DB AO_8542F1_IFJ_OBJ_JIRAISSUE and customfieldvalue we can observe values are intact so it is most likely the Jira and/or Insight indexes got corrupted during the upgrade someway.
• In Insight object view we can observe that someway the object key changed (while in DB is still intact). In the example screenshot DACZ-74 is the real object key:
  

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available