|negative||element will be focusable, but it should not be reachable via sequential keyboard navigation|
|0||element will be focusable and reachable through keyboard sequential navigation, but it's relative order is defined by the platform convention|
|positive||element must be focusable and accessible via sequential keyboard navigation; it's relative order will be defined by the attribute value: the sequential follow the increasing number of the |
The maximum value for
tabindex should not exceed 32767 as per W3C section 17.11.1
Unless specified default value is -1
An element with a value of 0, an invalid value, or no
tabindex value should be placed after the elements with a positive index in the sequential order of keyboard navigation.