I have a small portal in a popover that normally lives on the body part of many form layouts in my solution.
The portal displays a single related field that is configured as a button that navigates to the related record via a self-relation.
I can touch the tab key when in a field outside the portal (still in the popover) to go into and through all the rows of the portal to select the row and then activate the button with Return - which is exactly what I want.
However, if I move that same popover to the header part of a list view, although the portal displays the same related records, the tab key behaviour is changed. I can tab into the first row of the portal but the next touch of the tab key takes me out of the portal and not through the rows of the portal, which is not what I expected. I have checked that the tab order for the objects in the popover are sequential for that layout.
If I move the popover to a row in the list body, it again behaves like before, tabbing though the available rows, indicating the tab order is OK.
Disabling the scrollbar for the portal is ineffective.
Attempting to force the selection of the next portal row with a script trigger on each row calls the script step but the action is not performed and the next active object is again outside the portal.
Placing the popover in a top or bottom navigation part of a list view shows the same behaviour as in the header.
For now I have disabled navigation with the keyboard for this popover when in a header part of a list view but obviously I would prefer to have a consistent behaviour for this object across the solution, wherever it appears.