Check frameset frameborder and border attribute inheritance On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". missing frameborder attribute should inherit it PASS frames[0].offsetWidth is 150 PASS frames[1].offsetWidth is 150 inherited frameborder=no should inherit border=0 PASS frames[0].offsetWidth is 150 PASS frames[1].offsetWidth is 150 frameborder=yes and border should override inherited value PASS frames[0].offsetWidth is 145 PASS frames[1].offsetWidth is 145 inherited frameborder=0 should have border=0 even if specified differently PASS frames[0].offsetWidth is 150 PASS frames[1].offsetWidth is 150 bordercolor should inherit even if frameborder=0 PASS frames[0].offsetWidth is 145 PASS frames[1].offsetWidth is 145 PASS getComputedStyle(frameset).borderColor is "rgb(0, 128, 0)" PASS successfullyParsed is true TEST COMPLETE