Comment # 4 on bug 1099752 from Bernhard Dr. Friedrichs

It works now after the update

Hence that the debug-bar did not came back automatically - also not by manually
restoring the "default view".

I made a backup of ./config/QtProject
delete

let qtcreator make a new one

changed Settings\EnvironmentId=@ByteArray in QtCreator ini
and
in profiles.xml

<value type="QString" key="PE.Profile.Id"> ..
<variable>Profile.Default</variable>
  <value type="QString">  ..

That at least let you continue to work and spend not too mich time with
restoring profile setting 20 to 30 times ... depending of how many projects you
have