Disable OpenGL accumulation buffer when running under XWayland

diff --git a/Tcl/custom-definitions b/Tcl/custom-definitions
index 5267760..2635452 100644
--- a/Tcl/custom-definitions
+++ b/Tcl/custom-definitions
@@ -18,7 +18,12 @@
 # $XCRYSDEN_TOPDIR/Tcl/toglOpt.tcl
 # ------------------------------------------------------------------------
 
-#set toglOpt(accum)  false 
+if {[info exists ::env(XDG_SESSION_TYPE)] &&
+    $::env(XDG_SESSION_TYPE) eq "wayland"} {
+    set toglOpt(accum) false
+} elseif {[info exists ::env(WAYLAND_DISPLAY)]} {
+    set toglOpt(accum) false
+}
 #set toglOpt(stereo) none