bloated font size rendered in webkit based browsers

Recently after a complete ports update in FreeBSD-10-p7 X86_64, my BSD system is also infected with font problem under webkit browsers such as vimb and dwb or even xombrero. But the difference is while I have fuzzy rendring problem in webkit under Linux (1 , 2 ); under FreeBSD I have fuzzy fonts and bloated font rendering. (see the picture below). In any case what is the solution for bloated exploding font rendring in webkit.