Window 7, GTX 770 oc
Pressing Alt+I while hovering over a strip's Extrapolation value just crashes Blender.
Moving the strip causes the value to switch back to Hold.
In another file, I have a strip that's stuck in Hold Forward. No matter what I do, the tracks will only use Nothing or Hold Forward. If the box and changed to Hold any change (even temp/cancelled), will switch it back to Hold Forward (or None if that was set).
In this new example file, it's the opposite except if the value is set to Hold Forward, it will work and remain that until the strip is moved (temp/cancelled/permanent).