Index: head/x11-servers/xorg-server/pkg-message
===================================================================
--- head/x11-servers/xorg-server/pkg-message	(revision 539621)
+++ head/x11-servers/xorg-server/pkg-message	(revision 539622)
@@ -1,25 +1,35 @@
 [
 { type: install
   message: <<EOM
 Xorg-server has been installed.
 
 If your kernel is compiled with the EVDEV_SUPPORT option enabled
 (default starting from FreeBSD 12.1) it is recommended to enable evdev mode in
 pointer device drivers like ums(4) and psm(4). This will give improvements like
 better tilt wheel support for mice and centralized gesture support via
 xf86-input-synaptics or libinput drivers for touchpads.
 
 This is also needed for PS/2 devices to be properly detected by Xorg when
 moused service is disabled in /etc/rc.conf and kernel is compiled with
 EVDEV_SUPPORT.
 
 To enable evdev in such a device, run the following:
 
 # sysctl kern.evdev.rcpt_mask=6
 
 To make it persistent across reboots, add the following to /etc/sysctl.conf:
 
 kern.evdev.rcpt_mask=6
+
+In case you're using a serial mouse or any other mouse that *only* works over
+sysmouse(4) and moused(8) on an evdev enabled kernel, please run this:
+
+# sysctl kern.evdev.rcpt_mask=3
+
+To make it persistent across reboots, add to this /etc/sysctl.conf:
+
+kern.evdev.rcpt_mask=3
+
 EOM
 }
 ]