The language of Non-text Contrast specifically calls out "visual information required to identify...states." When users talk about a hover state, they are normally referring to a visual effect that takes place when the pointer is positioned over a control. However, there are a number of HTML components (such as buttons, checkboxes, radio buttons, and selects) which do not by default display any additional visual effects when the user moves a pointer control over them. The pointer itself, via its location, is the indicator of whether the user is hovering on a component. Therefore, additional author-supplied visual treatments for hover are not "required to identify" the hover state. Those treatments can be considered supplemental and do not themselves need to contrast 3:1 against the background.
+ +This is not to say that other hover effects are discouraged. For instance, some native components alter the shape of the pointer when it is hovering over a control; the pointer becomes an I-beam when it hovers over text inputs and text areas. There will be cases where some users may benefit from additional visual hover effects, such as bolding text or use of drop shadows. However, other users may find strong hover effects distracting. The key consideration for any hover effect is that it does not cause a component itself to lose sufficient contrast against adjacent colors, or cause the visual indicators for other states, such as focus or selection, to lose sufficient contrast.
+For designing focus indicators, selection indicators and user interface components that need to be perceived clearly, the following are examples that have sufficient contrast.