Apps open outside displays on external monitors (Yosemite iMac 27" 3.4ghz i7) I have two external monitors from my iMac, both are rotated in portrait mode. I assign apps to the outside displays via the dock so they open in a particular display.

When I open an App that is assigned to an external monitor, they will often open with their window either partially or completely outside of the display.  The only way to 'grab' them is via spaces.

Does anyone have a solution for this issue?
i have the same problem, i noticed that it happen if i start or resume my mac with the external display connected, if i connect it after the mac is wake up it behave normally.

Probably it fail to detect the correct setting for monitor during startup (or something messed it up as wake up)

So not a fix but at least you can work..