The left and right lateral positions, currently used, are with respect to the left and right vertical sides. Extra ones could be added with respect to the center (like those in Hint.css). For that purpose, a reference attribute with values side and center could be used. So, each up-left, up-right, down-left or down-right comes together with one of side (default) or center.
Arrow
Support for removing the arrow (like that in Tootik) !important
Support for other indicators such as half arrow (like that in Simptip) !beauty
Horizontal lateral positions
reference
attribute with valuesside
andcenter
could be used. So, eachup-left
,up-right
,down-left
ordown-right
comes together with one ofside
(default) orcenter
.Arrow
!important
half arrow
(like that in Simptip)!beauty
Note: For the sake of completeness and primacy ☻