The Apps don't break unless you save them with the height set to 20 -- then, the App's height will be 20.
Which means, yes, if you update the code on a surface, you also have to remember to change the '20' to the proper height before you save. If you've already saved with the height set to '20', you can go back and enter the right height and save it again. The box will still show a '20', but the App will save the height you entered.
There is no need to add gadgets.window.adjustHeight() to each of your Applications.
I'm not making light of the bug -- it's definitely a bug, and it definitely needs to be fixed, but there's no need to go through a lengthy process -- the bug will only affect Apps that get saved without setting the proper Height.