Various elements have `tabindex` > 0 in Prosilver, which means they are navigated to in a confusing and unintuitive order when using keyboard navigation.

Per https://webaim.org/techniques/keyboard/tabindex:
 

Important
tabindex values of 1+ must be avoided. These elements will receive keyboard focus before elements with no tabindex value (or tabindex="0") resulting in a navigation order that is different from the visual and/or screen reader order. Instead of using tabindex, simply adjust the page's source code order to support a logical navigation and reading order, then use CSS to adjust the visual presentation.