Why does fil­ter­ing by HTML el­e­ment, class or ID not pre­vent processing?

wp-​Typography does not have ac­cess to HTML stored in your theme files. It on­ly has ac­cess to the con­tent passed to it (i.e. post ti­tle and con­tent); it is un­able to de­ter­mine the greater con­tex­tu­al awareness.

If you try to fil­ter pro­cess­ing based on a class of the body el­e­ment — as an ex­am­ple — noth­ing will hap­pen. wp-​Typography does not see the body el­e­ment. wp-​Typography does fil­ter by HTML el­e­ment, class or ID for any markup present with­in the parsed con­tent. So if you do not want class noTypo processed, fil­ter­ing will on­ly oc­cur with­in the ti­tle or con­tent of your post or page.