Merge data from multiple Jira

Source Jira Cloud

1. Enable “Save checklist data to Jira custom fields” toggle Jira settings.
   This way, all checklist data will be stored in Jira custom fields and migrated automatically with other Jira data (the initial save might require a few hours if the switch was disabled before).

2. Export issues from Jira.
   There are several ways to do it (Jira backup-export, CSV, etc.)

Destination/merged/final Jira Cloud

When all Jira data is merged/imported to the destination Jira Cloud instance (most likely using Jira built-in export/import functionality), please take the following steps to import/activate the checklist data:

1. Import Jira data (it will create checklist custom fields).
   Please note the ID of the Checklist Text field.

2. Install Issue Checklist

3. New installation of Issue Checklist will create new Checklist Text field (you will have duplicate fields with those names as they were also imported from the old Jira instance).
   Please note the ID of the new custom field named “Checklist Text”

4. Enable “Save checklist data to Jira custom fields”

5. Copy content of the old custom field to the new one for all issues (or just all issues with the non-empty old custom field). You can find all issues containing checklist data in old custom fields using simple JQL, e.g.: cf[10159] is not empty (the number in square brackets is the ID of old/imported “Checklist Text” custom field)
   The copy can be performed in several ways, e.g.:

   1. through CSV import/export or

   2. using Script Runner or

   3. Jira built-in automation. 

When completed, all issues having non-empty checklist custom fields should also display a checklist as a list of checkboxes with progress bars, etc.