We don’t use tooltops
Why don’t we use tooltips?
Tooltips are indicative of poor UX design.
If there is important content that is required to understand the UI, the tooltip is a sub optimal approach to helping the user.
Tooltip acceptance criteria are impossible to define
The specific WAI-ARIA guidance isn’t clear and screen reader implementation will vary, so it’s impossible to create success criteria.
What should I do instead?
Put in the work to design and edit the UI language so that it’s self explanatory.
What if there’s no other way?
If you still have detailed information that needs to be displayed, consider putting it in a modal or an expander accordion component.