Tips from a reader indicate that the iPad 2’s new screen mirroring feature may not be as broadly supported as users might hope, due to certain third-party developers’ copyright concerns. Introduced by Apple at this week’s media event in San Francisco, iPad 2 screen mirroring enables an iPad 2 to display all of its screen contents on an HDMI port-equipped HDTV, duplicating whatever is being shown on the device’s 9.7” touchscreen.…