Comment 15 for bug 1714302

Revision history for this message
In , Bakhelit (bakhelit) wrote :

I can confirm that the workaround from comment 2 still works. I was hit by this bug recently when attempting to mirror my laptop screen and a projector at work (NEC P502HL-2: https://www.necdisplay.com/p/np-p502hl-2). Both support 1920x1080 resolution but refresh rates differ very slightly and as XFCE tries to find an exact refresh rate match it sets lower 1680x1050 resolution. Unfortunately the projector was really unhappy about this and started to flicker like mad:(. So I had to use the screens in a side by side configuration without mirroring (this made the presentation a bit less comfortable for me:).

I also tested this at home with my monitor (EIZO EV2313W: https://www.eizoglobal.com/support/db/products/model/EV2313W) and the result was similar. Although both screens also support 1920x1080 resolution the refresh rates differ very slightly too and thus XFCE finds an exact refresh rate match with 1680x1050 resolution. Fortunately my EIZO monitor worked flawlessly (as it always does) and did not produce any flickering stroboscope effects like that poor NEC projector:).

I also noticed a warning in my "~/.xsession-errors" file when working with the projector:
(xfwm4:782): xfwm4-WARNING **: output size (1680x1050) and logical screen size (3840x1080) do not match
and with the monitor:
(xfwm4:786): xfwm4-WARNING **: output size (1680x1050) and logical screen size (1920x2160) do not match

But I am not sure if these warnings are completely relevant for this bug or if it is a slightly different issue.

I will post the exact "xrandr -q" outputs for my laptop display with the projector and monitor in the following comments.