Dunst doesnt work if screen number >= amount of monitors on that screen

[mcz]

I have two X screens, :0.0 and :0.1 and I want to run dunst on the second one. When I try to run dunst, it exits with the message dunst: src/x11/screen.c:377: get_active_screen: Assertion `ret >= 0 && ret < screens_len' failed..
Running it on screen 0 works. The options "monitor" and "follow" don't change anything.

Some (maybe) useful info:

$ DISPLAY=:0 xrandr

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384
eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
   1920x1080     60.02*+  60.01    59.97    59.96    59.93
   1680x1050     59.95    59.88
   1400x1050     59.98
   1600x900      59.99    59.94    59.95    59.82
   (... more resolutions...)
   432x243       59.92    59.57
   320x240       60.05
   360x202       59.51    59.13
   320x180       59.84    59.32

$ DISPLAY=:0.1 xrandr

Screen 1: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384
HDMI-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 509mm x 286mm
   1920x1080     60.00*+
   1600x1200     60.00
   1680x1050     59.88
   1280x1024     75.02    60.02
   1440x900      59.90
   1280x800      59.91
   1024x768      75.03    60.00
   800x600       75.00    60.32
   640x480       75.00    59.94
   720x400       70.08
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)

I think the problem is as follows:
In src/x11/screen.c:randr_update() XRRMonitorInfo is used to get the number of Monitors on the DefaultScreen(xctx.dpy). The default screen is taken from the DISPLAY environment variable, which is :0.1, so the default Screen is 1. I have one active monitor on that screen, so screens_len gets set to 1.
Later, in src/x11/screen.c:screen_info() ret gets set from DefaultScreen() once again to determine what monitor to use (This is wrong, since screens != monitors). And because my screen's index isn't less than the number of active monitors on that screen, assert aborts.

Installation info

• Version: Dunst - A customizable and lightweight notification-daemon 1.5.0 (2020-07-23)
• Install type: package
• Distro and version: Arch Linux

[fwsmit]

Fixed by #809, closing.