qtcreator main menu invisible/inaccessible after ui designer session

[Rudolf Leitgeb]

As soon as I edit the ui designer page of qtcreator, the title menu becomes invisible and inaccessible. It does not even reappear after I leave ui designer page, a window resize also doesn't help, restarting qtcreator brings everything back to normal until I enter ui design mode the next time.

No obvious error messages are shown if I start and run qtcreator from the command line. The system is fully updated and uses stock version of all relevant binaries, libraries, and config files.
The command 'lsb_release -rd' returns:
Description: Ubuntu 17.04
Release: 17.04

The command 'apt-cache policy qtcreator' returns:
qtcreator:
  Installed: 4.1.0-3ubuntu1
  Candidate: 4.1.0-3ubuntu1
  Version table:
 *** 4.1.0-3ubuntu1 500
        500 http://at.archive.ubuntu.com/ubuntu zesty/universe amd64 Packages
        100 /var/lib/dpkg/status

The problem already exists with minimal projects, i.e. I can reproduce it by starting qtcreator, creating a new 'QT Widgets Application', using the default values in all further input fields until the project is created, then double clicking on mainwindow.ui in the file browser on the left hand side. As soon as the ui designer has started, the menu is gone until the next restart of qtcreator.

Expected behavior: regardless of UI actions I have a fully populated menu in the title bar which becomes visible as soon as I hover the mouse pointer over the title bar of the qtcreator window.

Observed behavior: after performing the actions stated above, I still have a window title bar with window manager decoration, the qtcreator menu, however, is gone.

[Rudolf Leitgeb (rudolf-leitgeb)]

Whatever happened, the bug appears to be no longer present in current ubuntu release 17.10. This may well be due to Ubuntu's switch to GNOME.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.