[Gambas-bugtracker] Bug #1501: Gambas IDE Dialogue Windows without Control Buttons under Mint 19 Mate

[bugtracker at gambaswiki.org]

http://gambaswiki.org/bugtracker/edit?object=BUG.1501&from=L21haW4-

Claus DIETRICH reported a new bug.

Summary
-------

Gambas IDE Dialogue Windows without Control Buttons under Mint 19 Mate

Type             : Request
Priority         : Medium
Gambas version   : 3.12
Product          : Unknown


Description
-----------

Hi
The default theme Mint-Y in my virtual Mint 19 Mate provides me with following problem in the Gambas-IDE V3.12.0.  
Following windows of the Gambas-IDE
    • Settings
    • Key short cuts
    • Help
    • Search/ replace
are displayed without any close- or min/max-button and the windows cannot be controlled by clicking into the control area. So the control buttons are really not there and not just invisible. 
This problem occurs only in the Gambas IDE. Please find attached a screenshot as left-right comparison (left=LibreOffice V6.1.3.2 – with close button , right=Gambas-IDE V3.12 – without close button).

As a workaround for Mint 19 Mate, one can either choose a different theme (i.e. Mint-X) or just select a different window frame theme than Mint-Y. This problem doesn‘t occur in Mint 19 Cinnamon and earlier Mint Mate versions.
However, a comparison with Mint 19 Xfce delivered another surprise - the same Gambas-IDE-Settings-Dialogue shows an additional and working min-max-Button, which I haven‘t seen in my life before - see attached screenshot.

In order to be sure and to find a generic solution, it would be useful if the Gambas developers would reconfirm the actual cause of the problem, whether in Mint, in the Gambas-IDE or both.

Please take Note: The attached system information lists the unexpected entry "Theme=Windows", although the theme Mint-Y is activated, the Windows theme was de-installed and the Gambas-IDE restarted(?).
 
With best regards
Crabman


System information
------------------

[System]
Gambas=3.12
OperatingSystem=Linux
Kernel=4.15.0-43-generic
Architecture=x86_64
Distribution=Linux Mint 19 Tara
Desktop=MATE
Theme=Windows
Language=de_DE.UTF-8
Memory=3945M

[Libraries]
Cairo=libcairo.so.2.11510.0
Curl=libcurl.so.4.5.0
DBus=libdbus-1.so.3.19.4
GStreamer=libgstreamer-1.0.so.0.1401.0
GTK+2=libgtk-x11-2.0.so.0.2400.32
GTK+3=libgtk-3.so.0.2200.30
OpenGL=libGL.so.1.0.0
Poppler=libpoppler.so.73.0.0
QT4=libQtCore.so.4.8.7
QT5=libQt5Core.so.5.9.5
SDL=libSDL-1.2.so.0.11.4
SQLite=libsqlite3.ssurprise o.0.8.6

[Environment]
CLUTTER_BACKEND=x11
COMPIZ_CONFIG_PROFILE=mate
DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus
DEFAULTS_PATH=/usr/share/gconf/mate.default.path
DESKTOP_SESSION=mate
DISPLAY=:0
GB_GUI=gb.qt4
GDMSESSION=mate
GDM_LANG=de_DE
GPG_AGENT_INFO=/run/user/1000/gnupg/S.gpg-agent:0:1
GTK_MODULES=gail:atk-bridge
GTK_OVERLAY_SCROLLING=0
HOME=<home>
LANG=de_DE.UTF-8
LANGUAGE=de_DE.UTF-8
LOGNAME=<user>
MANDATORY_PATH=/usr/share/gconf/mate.mandatory.path
MATE_DESKTOP_SESSION_ID=this-is-deprecated
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games
PWD=<home>
QT_ACCESSIBILITY=1
QT_AUTO_SCREEN_SCALE_FACTOR=0
QT_QPA_PLATFORMTHEME=qt5ct
QT_SCALE_FACTOR=1
SESSION_MANAGER=local/<hostname>:@/tmp/.ICE-unix/1207,unix/<hostname>:/tmp/.ICE-unix/1207
SHELL=/bin/bash
SHLVL=0
SSH_AGENT_PID=1326
SSH_AUTH_SOCK=/run/user/1000/keyring/ssh
TZ=:/etc/localtime
USER=<user>
XAUTHORITY=<home>/.Xauthority
XDG_CONFIG_DIRS=/etc/xdg/xdg-mate:/etc/xdg
XDG_CURRENT_DESKTOP=MATE
XDG_DATA_DIRS=/usr/share/mate:<home>/.local/share/flatpak/exports/share:/var/lib/flatpak/exports/share:/usr/local/share:/usr/share
XDG_GREETER_DATA_DIR=/var/lib/lightdm-data/<user>
XDG_RUNTIME_DIR=/run/user/1000
XDG_SEAT=seat0
XDG_SEAT_PATH=/org/freedesktop/DisplayManager/Seat0
XDG_SESSION_DESKTOP=mate
XDG_SESSION_ID=c1
XDG_SESSION_PATH=/org/freedesktop/DisplayManager/Session0
XDG_SESSION_TYPE=x11
XDG_VTNR=7