Unable to launch Calibre Debian 9 AMD64QXcbConnection: XCB error

[Dr. Carlo Valle]

When I try to launch the application program I get the following error. I installed the Debian package from synaptic which is version 2.75.1, I then tried version 3.30.0. Both generated this error. I uninstalled and installed a couple of times to make sure.

Qt: Session management error: None of the authentication protocols specified are supported
QWidget::setMinimumSize: (/Wizard) Negative sizes (-402653024,0) are not possible
QWidget::setMinimumSize: (/Wizard) Negative sizes (0,-626349394) are not possible
QWidget::setMaximumSize: (/Wizard) Negative sizes (-402128897,16777215) are not possible
QWidget::setMaximumSize: (/Wizard) Negative sizes (0,-609572179) are not possible
QWidget::setMinimumSize: (/QLabel) The largest allowed size is (16777215,16777215)
QWidget::setMinimumSize: (/QWidget) Negative sizes (-492131605,55) are not possible
QXcbConnection: XCB error: 2 (BadValue), sequence: 405, resource id: 0, major code: 1 (CreateWindow), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 406, resource id: 12582916, major code: 2 (ChangeWindowAttributes), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 407, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 408, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 409, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 411, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 412, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 413, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 416, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 420, resource id: 12582916, major code: 2 (ChangeWindowAttributes), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 421, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 422, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 423, resource id: 12582916, major code: 20 (GetProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 427, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 428, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 431, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 434, resource id: 12582916, major code: 18 (ChangeProperty), minor code: 0

[Kovid Goyal (kovid)]

That looks like a problem with your X server, it is reporting incorrect
screen size/DPI information to Qt. I'm not an expert on the X server so
I cannot offer you more information. In general, try using a different graphics
driver or try setting the monitor dimensions and DPI manually in
Xorg.conf

You can also try setting the environment variable

QT_AUTO_SCREEN_SCALE_FACTOR=0

to tell Qt to not do scaling with monitor dpi

 status invalid