diff --git a/scripts/manual.sh b/scripts/manual.sh
index 56e9b320..f8e2f4cc 100755
--- a/scripts/manual.sh
+++ b/scripts/manual.sh
@@ -2,4 +2,5 @@
 cargo build
 
 ./target/debug/oxipng -V > MANUAL.txt
-./target/debug/oxipng --help >> MANUAL.txt
+#Redirect all streams to prevent detection of the terminal width and force an internal default of 100
+./target/debug/oxipng --help >> MANUAL.txt 2>/dev/null </dev/null