Success Criterion 1.4.13 Content on Hover or Focus *

Understanding Success Criterion: 

Where receiving and then removing pointer hover or keyboard focus triggers additional content to become visible and then hidden, the following are true:
A mechanism is available to dismiss the additional content without moving pointer hover or keyboard focus, unless the additional content communicates an input error or does not obscure or replace other content;
If pointer hover can trigger the additional content, then the pointer can be moved over the additional content without the additional content disappearing;
The additional content remains visible until the hover or focus trigger is removed, the user dismisses it, or its information is no longer valid.

Accessibility Level: 
Exceptions to Success Criterion: 

The visual presentation of the additional content is controlled by the user agent and is not modified by the author.

Intent of Success Criterion: 

Additional content that appears and disappears in coordination with keyboard focus or pointer hover often leads to accessibility issues. Reasons for such issues include:
1. the user may not have intended to trigger the interaction
2. the user may not know new content has appeared
3. the new content may intefere with a user's ability to do a task
Examples of such interactions can include custom tooltips, sub-menus and other nonmodal popups which display on hover and focus. The intent of this success criterion is to ensure that authors who cause additional content to appear and disappear in this manner must design the interaction in such a way that users can:
• perceive the additional content AND
• dismiss it without disrupting their page experience.
There are usually more predictable and accessible means of adding content to the page, which authors are recommended to employ. If an author does choose to make additional content appear and disappear in coordination with hover and keyboard focus, this success criterion specifies three conditions that must be met:
• dismissable
• hoverable
• persistent
Each of these is discussed in a separate section.

Specific Benefits of Success Criterion: 

• Users with low vision who view content under magnification will be better able to view content on hover or focus without reducing their desired magnification.
• Users who increase the size of mouse cursors via platform settings or assistive technology will be able to employ a technique to view obscured content on hover.
• Users with low vision or cognitive disabilities will have adequate time to perceive additional content appearing on hover or focus and to view the trigger content with less distraction.
• users with low pointer accuracy will be able to more easily dismiss unintentionally-triggered additional content