Add null checks to client prefs checks

client.prefs. -> client?.prefs?.

code/modules/admin/admin.dm

@@ -104,7 +104,7 @@
 	if(M.client)
 		body += "| <A href='?_src_=holder;[HrefToken()];sendtoprison=[REF(M)]'>Prison</A> | "
 		body += "\ <A href='?_src_=holder;[HrefToken()];sendbacktolobby=[REF(M)]'>Send back to Lobby</A> | "
-		var/muted = M.client.prefs.muted
+		var/muted = M.client?.prefs?.muted
 		body += "<br><b>Mute: </b> "
 		body += "\[<A href='?_src_=holder;[HrefToken()];mute=[M.ckey];mute_type=[MUTE_IC]'><font color='[(muted & MUTE_IC)?"red":"blue"]'>IC</font></a> | "
 		body += "<A href='?_src_=holder;[HrefToken()];mute=[M.ckey];mute_type=[MUTE_OOC]'><font color='[(muted & MUTE_OOC)?"red":"blue"]'>OOC</font></a> | "

code/modules/admin/secrets.dm

@@ -743,7 +743,7 @@
 		if (length(players))
 			var/mob/chosen = players[1]
 			if (chosen.client)
-				chosen.client.prefs.copy_to(spawnedMob)
+				chosen.client?.prefs?.copy_to(spawnedMob)
 				spawnedMob.key = chosen.key
 			players -= chosen
 		if (ishuman(spawnedMob) && ispath(humanoutfit, /datum/outfit))

code/modules/admin/sound_emitter.dm

@@ -142,7 +142,7 @@
 		if(SOUND_EMITTER_GLOBAL)
 			hearing_mobs = GLOB.player_list.Copy()
 	for(var/mob/M in hearing_mobs)
-		if(M.client.prefs.toggles & SOUND_MIDI)
+		if(M.client?.prefs?.toggles & SOUND_MIDI)
 			M.playsound_local(M, sound_file, sound_volume, FALSE, channel = CHANNEL_ADMIN, pressure_affected = FALSE)
 	if(user)
 		log_admin("[ADMIN_LOOKUPFLW(user)] activated a sound emitter with file \"[sound_file]\" at [AREACOORD(src)]")

code/modules/admin/verbs/deadsay.dm

@@ -26,7 +26,7 @@
 	for (var/mob/M in GLOB.player_list)
 		if(isnewplayer(M))
 			continue
-		if (M.stat == DEAD || (M.client && M.client.holder && (M.client.prefs.chat_toggles & CHAT_DEAD))) //admins can toggle deadchat on and off. This is a proc in admin.dm and is only give to Administrators and above
+		if (M.stat == DEAD || (M.client && M.client.holder && (M.client?.prefs?.chat_toggles & CHAT_DEAD))) //admins can toggle deadchat on and off. This is a proc in admin.dm and is only give to Administrators and above
 			to_chat(M, rendered)
 
 	SSblackbox.record_feedback("tally", "admin_verb", 1, "Dsay") //If you are copy-pasting this, ensure the 2nd parameter is unique to the new proc!

code/modules/admin/verbs/one_click_antag.dm

@@ -32,7 +32,7 @@
 /datum/admins/proc/isReadytoRumble(mob/living/carbon/human/applicant, targetrole, onstation = TRUE, conscious = TRUE)
 	if(applicant.mind.special_role)
 		return FALSE
-	if(!(targetrole in applicant.client.prefs.be_special))
+	if(!(targetrole in applicant.client?.prefs?.be_special))
 		return FALSE
 	if(onstation)
 		var/turf/T = get_turf(applicant)
@@ -412,7 +412,7 @@
 
 				//Spawn the body
 				var/mob/living/carbon/human/ERTOperative = new ertemplate.mobtype(spawnloc)
-				chosen_candidate.client.prefs.copy_to(ERTOperative)
+				chosen_candidate.client?.prefs?.copy_to(ERTOperative)
 				ERTOperative.key = chosen_candidate.key
 
 				if(ertemplate.enforce_human || ERTOperative.dna.species.dangerous_existence) // Don't want any exploding plasmemes

code/modules/admin/verbs/playsound.dm

@@ -33,7 +33,7 @@
 	message_admins("[key_name_admin(src)] played sound [S]")
 
 	for(var/mob/M in GLOB.player_list)
-		if(M.client.prefs.toggles & SOUND_MIDI)
+		if(M.client?.prefs?.toggles & SOUND_MIDI)
 			var/user_vol = M.client.chatOutput.adminMusicVolume
 			if(user_vol)
 				admin_sound.volume = vol * (user_vol / 100)

code/modules/admin/verbs/pray.dm

@@ -11,7 +11,7 @@
 		return
 	log_prayer("[src.key]/([src.name]): [msg]")
 	if(usr.client)
-		if(usr.client.prefs.muted & MUTE_PRAY)
+		if(usr.client?.prefs?.muted & MUTE_PRAY)
 			to_chat(usr, "<span class='danger'>You cannot pray (muted).</span>")
 			return
 		if(src.client.handle_spam_prevention(msg,MUTE_PRAY))

code/modules/admin/verbs/randomverbs.dm

@@ -288,7 +288,7 @@
 		for(var/mob/M in GLOB.player_list)
 			if(M.stat != DEAD)
 				continue	//we are not dead!
-			if(!(ROLE_ALIEN in M.client.prefs.be_special))
+			if(!(ROLE_ALIEN in M.client?.prefs?.be_special))
 				continue	//we don't want to be an alium
 			if(M.client.is_afk())
 				continue	//we are afk