Manually ports /tg/'s darkclick code.

https://github.com/tgstation/-tg-station/pull/10272 by Razharas.

code/modules/client/client defines.dm

@@ -46,3 +46,5 @@
 	var/related_accounts_cid = "Requires database"	//So admins know why it isn't working - Used to determine what other accounts previously logged in from this computer id
 
 	preload_rsc = 0 // This is 0 so we can set it to an URL once the player logs in and have them download the resources from a different server.
+	var/global/obj/screen/click_catcher/void
+	

code/modules/client/client procs.dm

@@ -159,6 +159,10 @@
 
 	send_resources()
 	nanomanager.send_resources(src)
+	
+	if(!void)
+		void = new()
+	screen += void
 
 	if(prefs.lastchangelog != changelog_hash) //bolds the changelog button on the interface so we know there are updates.
 		src << "<span class='info'>You have unread updates in the changelog.</span>"