it's safe now to disable ignoreBuildErrors.

for example if i answered with 3
old behavior: the next question will have the 3rd button checked.
new behavior: the next question will have no answer focused.

the default choice now is null, the button will be disabled as long as
the choice is null.

app is able to:
  make a quiz from image/doc content
  make a quiz that includes single/double quotes with no crash/error
  caused by parsing json