One issue with CheckUser is that issues crop up when the extension encounters a DB with a large number of edits and actions. This cannot adequately done in CI tests as the setup time would add too much time to set-up each test. However, having a instance of CheckUser that has a DB filled with varying actions means that in code review and QA the extension can be tested against an environment that isn't usually present on a local testing wiki.
Acceptance criteria
- Create a maintenance script used only for testing that adequately fills the DB with events in CheckUser
QA Results - Local
| AC | Status | Details |
|---|---|---|
| 1 | ✅ | https://phabricator.wikimedia.org/T342371#9128336 |

