Steps to reproduce editor freezing:
1. Open user attached project "CrashProject II.zip"
2. Enter play mode
3. Wait a couple of seconds for the button to appear and press it
4. Editor freezes

Expected: The element gets re-parented to the original canvas without issue
Actual: Editor freezes for an unspecified amount of time, sometimes comes back, sometimes doesn't

Reproduced on: 5.5.4p1, 5.6.3f1, 2017.1.0p3, 2017.2.0b6, 2017.3.0a3

Steps to reproduce image not appearing after reparenting and enabling again:
1. Open user attached project "CrashProject III.zip"
2. Enter play mode
3. Wait a couple of seconds for the button to appear and press it
4. Graphic disappears and is re-parented to the old canvas
5. Try to enable all the elements in the hierarchy so that the image appears
6. It doesn't

Expected: The element should appear normally when enabled after the reparenting
Actual: The element remains invisible, even though by all the settings it should be visible and clickable

Reproduced on: 5.5.4p1, 5.6.3f1, 2017.1.0p3, 2017.2.0b6, 2017.3.0a3