I correct myself the bug by changing the virtual resolution in the Xorg :
Section "Screen"
Identifier "Configured Screen Device"
Device "Configured Video Device"
SubSection "Display" Virtual 2560 2048 EndSubSection
EndSection
Section "Device"
Identifier "Configured Video Device"
EndSection
Why the default resolution didn't was 2560 ? I also think that gnome-display-prophetie didn't change xorg.conf when I apple the dual screen extended configuration.
I correct myself the bug by changing the virtual resolution in the Xorg :
Virtual 2560 2048
EndSubSection
Section "Screen"
Identifier "Configured Screen Device"
Device "Configured Video Device"
SubSection "Display"
EndSection
Section "Device"
Identifier "Configured Video Device"
EndSection
Why the default resolution didn't was 2560 ? I also think that gnome-display- prophetie didn't change xorg.conf when I apple the dual screen extended configuration.