try replacing with grep

lgsm/functions/mods_core.sh

@@ -190,24 +190,16 @@ fn_postinstall_tasks(){
 	# Output to the user
 	fn_print_information_nl "Rearranging ${modcommand}-files.list"
 	fn_script_log_info "Rearranging ${modcommand}-files.list"
-	smremovefromlist="cfg;addons;"
+	removefromlist="cfg;addons;"
 	# Loop through every single line to find any of the files to remove from the list
 	# that way these files won't get removed upon update or uninstall
-	fileslistline=1
-	while [ $fileslistline -le $modsfilelistsize ]; do
-		testline="$(sed "${fileslistline}q;d" "${modsdatadir}/${modcommand}-files.list")"
-		# How many elements to remove from list
-		smremoveamount="$(echo "${smremovefromlist}" | awk -F ';' '{ print NF }')"
-		# Test all subvalue of "modkeepfiles" using the ";" separator
-		for ((filesindex=1; filesindex < ${smremoveamount}; filesindex++)); do
-			# Put current file into test variable
-			smremovetestvar="$( echo "${smremovefromlist}" | awk -F ';' -v x=${filesindex} '{ print $x }' )"
-			# If it matches
-			if [ "${testline}" == "${smremovetestvar}" ]; then
-				# Then delete the line!
-				sed -i "/${testline}/d" "${modsdatadir}/${modcommand}-files.list"
-			fi
-		done
-		let fileslistline=fileslistline+1
+	# How many elements to remove from list
+	smremoveamount="$(echo "${removefromlist}" | awk -F ';' '{ print NF }')"
+	# Test all subvalue of "modkeepfiles" using the ";" separator
+	for ((filesindex=1; filesindex < ${smremoveamount}; filesindex++)); do
+		# Put current file into test variable
+		rmtestvar="$( echo "${removefromlist}" | awk -F ';' -v x=${filesindex} '{ print $x }' )"
+		# Remove matches
+		grep -vFf ${modsdatadir}/${modcommand}-files.list "${rmtestvar}" > ${modsdatadir}/${modcommand}-files.list
 	done
 }