NGUI buttons stop responding after game loses and regains focus, on Android Galaxy Tab 2

On an Android Galaxy Tab II, when my game is running and then loses focus (by pressing “Home”, by pressing the power button to turn off the screen, by switching to another running app in the background, etc.) and then regains focus, NGUI buttons are not responding.

I saw a similar problem that used to happen with EZGUI, here, so I tried replacing all of NGUI’s realtimeSinceStartup with Time.time - didn’t help.

I also tried implementing OnApplicationFocus that re-enables all colliders, and although the event was run in the Editor, it doesn’t help on the tablet.

Any ideas?

So as not to waste anyone’s time, I’ll answer myself:

A Unity update caused a bug in several plugins. All plugins’ developers issued a patch and eventually a stable version that fixed this.