Indexed Navigation with Tab per Daniel

Press Ctrl + \ to index selectable elements on the current web page. This is the indexed view.
While in the indexed view, enter the number of an index and hit the \ key. That indexed element will be selected.
Press Ctrl + \ again to exit the indexed view.

Note that if the webpage override any of the keys used, this extension may not work as intended (e.g. Youtube as of 2023-07 overrides number keys for navigating within a video).