Some HTML elements have a specific set of valid values for some attributes.
For instance the elements: a, area, link, or form all have an attribute called rel.
There is a fixed list of values that have any meaning for this attribute on these tags (see MDN).
To help with minimizing confusion while reading code, only the appropriate values should be on each attribute.
This rule aims to remove invalid attribute values.
The options is a list of attributes to check. Defaults to ["rel"].
When you don't want to enforce attribute value correctness.