diff --git a/code/datums/datumvars.dm b/code/datums/datumvars.dm
index cd4363d9dff..3f6cb900988 100644
--- a/code/datums/datumvars.dm
+++ b/code/datums/datumvars.dm
@@ -411,7 +411,7 @@ body
 
 	else if(href_list["datumrefresh"])
 		var/datum/DAT = locate(href_list["datumrefresh"])
-		if(!istype(DAT, /datum))
+		if(!DAT) //can't be an istype() because /client etc aren't datums
 			return
 		src.debug_variables(DAT)