plugging external display starts mirror mode while xfce4-display-settings shows mirror checkbox unchecked

Submitted by Andrej Kvasnica

Assigned to Jérôme Guelfucci

Description

Created attachment 7226 xfce4-display-settings showing Mirror on the preview but no Mirror checkbox checked

The default external display behaviour after pluging new device was "blank on the external display" until one decided to use "Extend to right" (preferred) or "Mirror".

After upgrading to Fedora 26 (XFCE 4.12) the default display settings changed. After external display plugs in, it:

starts the half-assed Mirror mode
sometimes moves the main panel to the external display (which is not what the mirror mode does too) so it seems more like an error than intention
minimal settings (the xfce4-display-settings -m) indicates the Mirror mode
full settings (xfce4-display-settings) shows not Mirror mode checkox checked but shows Mirror mode on screen preview

When I manually select "Extend to right" in minimal mode it just starts working in extend mode. When I play with other modes in minimal settings mode it mainly gets mad selecting wrong resolution for primary display.

The right behaviour is to show the settings but do not mirror the display, at least not that strange way it does now.

Attachment 7226, "xfce4-display-settings showing Mirror on the preview but no Mirror checkbox checked":

Version: 4.12.1