Can you try creating that file and see if xorg crashes on you after reboot?
It does here on up to date Manjaro XFCE stable:
[ 14.386] (II) Initializing extension VNC
[ 14.386] (EE)
[ 14.386] (EE) Backtrace:
[ 14.386] (EE) 0: /usr/lib/Xorg (dri3_send_open_reply+0xdd) [0x55fd4d841bed]
[ 14.387] (EE) 1: /usr/lib/libc.so.6 (__sigaction+0x50) [0x7f367c731a00]
[ 14.387] (EE) 2: /usr/lib/Xorg (xf86OptionValue+0xb) [0x55fd4d84e54b]
[ 14.387] (EE) 3: /usr/lib/xorg/modules/extensions/libvnc.so (vncExtensionInit+0xa31) [0x7f367bd8b2f1]
[ 14.388] (EE) 4: /usr/lib/Xorg (InitExtensions+0x89) [0x55fd4d72df69]
[ 14.388] (EE) 5: /usr/lib/Xorg (SProcXkbDispatch+0x1809) [0x55fd4d721094]
[ 14.388] (EE) 6: /usr/lib/libc.so.6 (__libc_init_first+0x90) [0x7f367c71c290]
[ 14.389] (EE) 7: /usr/lib/libc.so.6 (__libc_start_main+0x8a) [0x7f367c71c34a]
[ 14.389] (EE) 8: /usr/lib/Xorg (_start+0x25) [0x55fd4d7224b5]
[ 14.389] (EE)
[ 14.389] (EE) Segmentation fault at address 0x100000011
[ 14.389] (EE)
Fatal server error:
[ 14.389] (EE) Caught signal 11 (Segmentation fault). Server aborting
[ 14.389] (EE)
You seem to be also wanting to share your main display :0; note this is very easily done by adding simply e.g.
/usr/bin/x0vncserver -PasswordFile /home/<user>/.vnc/passwd
to for example your desktop startup applications (in XFCE, under "Session and Startup’) after generating said ~/.vnc/passwd with as said <user>, vncpasswd.
1 Like
Shot in the dark: look into DRI3. Maybe try disabling it, or change some related settings, etc.
If that’s to Tribble fair enough, but note that I am personally very much content with not setting up VNC via xorg.conf 
X11 is abandonware at this point; who cares about corner-cases like that…
Depends on one’s definition of “active” I guess, although admittedly I should have said that X server is abandonware; X11-the-protocol will in a walking-dead sort of way walk on for some time so as to support legacy applications.
But e.g. It's Time To Admit It: The X.Org Server Is Abandonware - Phoronix – and certainly I will in any case feel very free to not anymore care about some corner-case VNC extension that nobody other than people following the Arch Linux Wiki uses anyway…
So the Arch Linux Wiki has outdated information?
Probably not. I noticed it said that the extension route “provides better performance” which it likely in some sense does.
What the Arch Linux Wiki in any case has is lots of “I use Arch BTW” information that anyone should feel free to at any time prefer to go read over, say, popping a few of one’s youth pimples but which I myself tend to run through a bit of a filter first.
I share my desktop on this system I’m typing on over VNC and the explicit x0vncserver route works for me and has for a very, very long time. Performance is something that I can’t in the context care one whit about.