Point of Failure
The tabindex attribute should not be used to create a tab order that does not preserve meaning and operability
Automation
Linting
Automated linting exists. See the ember-template-lint library for the no-positive-tabindex rule.
Testing
See the axe-core library for the tabindex rule.
Developer Authored Test
Developers should ensure that their code does not violate this rule, and write a test that prevents regressions in code if it is later changed.
Manual Test
Review page and ensure the point of failure does not exist, inspecting the DOM where required.