* * Refresh the footer instantly when changing the prefix, separator, or
formatting.
* Allow setting the container height (formerly
DMINIBAR_CONTAINER_HEIGHT)
* Allow setting the container bottom padding (formerly 1 flex pixel)
* Refactor ReaderFooter:applyFooterMode
Handle toggling the genFooterText function even in all at once mode
Make sure the layout is properly reset when changing visibility state,
to avoid inconsistencies with complex layouts.