By tim.plunkett on
Change record status: 
Published (View all published change records)
Project: 
Drupal core
Introduced in branch: 
9.3.x
Introduced in version: 
9.3.0-alpha1
Issue links: 
https://www.drupal.org/node/3091870
Description: 

Previously, any JavaScript error that occurs that did not interfere with the functionality of the test was ignored.

Now those errors will be surfaced to the test runner.
In Drupal 9.3.x those will be triggered as a deprecation, allowing modules to address the problems.
In Drupal 10.0.x those will count as test failures.

To suppress any handling of these errors, add the following to your test class:

protected $failOnJavascriptConsoleErrors = FALSE;

As part of this change the testing infrastructure module js_deprecation_log_testhas been renamed to js_testing_log.

Impacts: 
Module developers
Themers