diff --git a/common-tasks/usb.md b/common-tasks/usb.md
index bfd935fd..0b221dc2 100644
--- a/common-tasks/usb.md
+++ b/common-tasks/usb.md
@@ -112,7 +112,7 @@ opt to create a USB qube during installation. This also occurs automatically if
 you choose to [create a USB qube] using the `qubesctl` method, which is the
 first pair of steps in the linked section.)
 
-**Warning** USB keyboard cannot be used to type the disk passphrase
+**Warning:** USB keyboard cannot be used to type the disk passphrase
 if USB controllers were hidden from dom0. Before hiding USB controllers
 make sure your laptop keyboard is not internally connected via USB
 (by checking output of `lsusb` command) or that you have a PS/2 keyboard at hand