MDL-76246 adds a required parameter after an optional one to the init function of grade/amd/src/searchwidget/basewidget.js
This js class was added in Moodle 4.1 and so we can't just add parameters in this way.

The registerListenerEvents() function now also looks for data-input-element on line 120 which did not exist in 4.1 and also breaks backwards compatibility.

Replication steps:

1. Install the following local plugin https://github.com/abgreeve/local_gradeselectortest on a Moodle 4.1 branch.
2. Go to a course and in the more menu of the secondary navigation click "Selector test"
3. Click the selector "Select an item" and select an item
4. The page should refresh and there should be a message that says "Item {1}

   was selected" where 1 can change depending on the item selected.

5. Upgrade to current master
6. Repeat steps 2 - 4

• Expected result: Everything works as it did in Moodle 4.1
• Actual result: Errors, and no ability to select an item.

There is something additional to what I noted above that stop the selection of an item working. Please make sure that the existing functionality is maintained with fixes made on this issue.