I’ve experienced a problem like this twice in the last six weeks now with my Surface Pro 3 (i5, 256gb).
Mine snaps to the top right corner and then closes any full screen programs!
Through a combination of things I got it resolved the first time, and I think/hope I’ve fixed it again this time. The bits that seem to do the trick are: uninstall the bluetooth drivers, uninstall the surface pen and arc touch mouse drivers (if you have one), then perform a two button reset (hold volume up and power button for about 30 seconds, you will see some screens flick on and off (including a screen with text that you likely won't have seen before), but don’t release the buttons until the screen is off and stays off. Then press the power on button. It should reinstall all the bluetooth and pen drivers and have cleared the kernel cache. You will likely have to go to the microsoft app store to download the arc touch mouse app again. Hope this helps