The style editor bound variables to paint colors, shadow colors, blur
radii and grid sizes, but a text style's fields took variables only
through style.bind. The font and font style menus now start with Apply
variable, which opens the picker on string variables, and the size, line
height and letter spacing fields show a variable button on hover for
number variables, as the Design panel's number fields do. A bound field
shows its variable's chip in place of the value, as in the Design
panel. A click on the chip picks another variable, and its detach
button unbinds it.