Windows tablet has no keyboard for shortcuts typing. Is any way make it shown as icon?
Home / Show Facing and Book View in Toolbar
Amongst adding hundreds of other icons Facing and Book view has been requested for example here https://github.com/sumatrapdfreader/sumatrapdf/issues/1117,
The Principle was not to add any more icons than were essential to a keyboard driven viewer, however with the introduction of tablets that use virtual keyboards that is seen as more problematic, and even the developer agrees more user choice is needed see https://github.com/sumatrapdfreader/sumatrapdf/issues/734