Bug#906290: kde-full: several KDE applications hang shortly after start

[tdowning <tdowning@bomgar.com>]

Package: kde-full
Version: 5:102
Severity: important

Dear Maintainer,

On 14 August 2018 I performed apt-get update; apt-get upgrade.  The last
date of update/upgrade was aprox 3-4 weeks earlier.

Before the 14 August upgrade I observed no bugs other than a minor, infrequent
plasma desktop issue.  After the upgrade, KDE applications no longer operate
normally. 

All KDE apps start, and function normally for a short time. They then cease
to be responsive to either user input, window manager operations, or network
driven input.  Clicking the title-bar 'quit' icon will eventually result in
the "not responding" dialog.

The time the app runs before hang is usually less than one minute, but sometimes
can be longer; rarely more than 15 minutes. Amount of user input does not seem
to correlate with how quickly the hung state occurs.

Not all KDE apps suffer the problem, notable Konsole has operated normally. Kmail,
Konqueror, KPat -), are notable apps that suffer the problem.

I have not seen any non-KDE applications have this problem.

FWIW, running KMail from console reveals the message:

    QFont::setPixelSize: Pixel size <= 0 (0)

repeated 50-100 times rapidly, while the app is displayed by idle.  After this
KMail is hung.

Please feel free to contact me if I can be of any assistance. I haven't done any
KDE development in years, but I still do C++/linux development.

Thanks

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.17.0-1-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE= (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages kde-full depends on:
ii  kde-plasma-desktop           5:102
ii  kde-standard                 5:102
ii  kdeadmin                     4:17.08.3+5.102
ii  kdeedu                       4:17.08.3+5.102
ii  kdegames                     4:17.08.3+5.102
ii  kdegraphics                  4:17.08.3+5.102
ii  kdemultimedia                4:17.08.3+5.102
ii  kdenetwork                   4:17.08.3+5.102
ii  kdepim                       4:17.12.3+5.102
ii  kdeutils                     4:17.08.3+5.102
ii  plasma-workspace-wallpapers  4:5.13.1-1

Versions of packages kde-full recommends:
ii  kdeaccessibility  4:17.08.3+5.102
ii  kdesdk            4:17.08.3+5.102
ii  kdetoys           4:17.08.3+5.102
ii  kdewebdev         4:17.08.3+5.102

Versions of packages kde-full suggests:
pn  calligra  <none>
ii  xorg      1:7.7+19

-- no debconf information