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README.md

@@ -1,13 +1,17 @@
 # AutoAuth for UCLA
 Speed up UCLA Single Sign-On. © 2018 Kevin Hsieh. All Rights Reserved. 
 
-- This is a WebExtension designed for Firefox and Chrome. To install, please
-  go to Firefox Add-ons or the Chrome Web Store.
+- This is a WebExtension designed for Firefox and Chrome. To install, please go
+  to Firefox Add-ons or the Chrome Web Store.
 - For Multi-Factor Authentication (MFA) users, you can give AutoAuth your next
   10 SMS passcodes and it will automatically enter them until you need new
   passcodes. AutoAuth also automatically checks "Remember me for 12 hours" when
-  it's available. It's still recommended that you use Duo Push when away from
-  your primary computer.
-- Firefox only: AutoAuth automatically signs in with your UCLA Logon ID and
-  UCLA Logon Password if your browser is set to fill them in automatically.
+  it's available.
+- Usage: Sign in normally. On the MFA screen, if AutoAuth prompts you to enter
+  new passcodes, then press "Text me new codes" and enter the 10 passcodes you
+  receive. It's recommended that you use Google Voice or iMessage in order to
+  easily copy-paste the codes, and that you continue using Duo Push when away
+  from your primary computer.
+- Firefox only: AutoAuth also automatically signs in with your UCLA Logon ID
+  and UCLA Logon Password if your browser is set to fill them in automatically.
 - Uses graphic(s) from [Material Design](https://material.io/icons/).

auto-mfa.js

@@ -89,7 +89,10 @@ function autoFill(doneReset) {
  */
 function setPasscodes() {
     let passcodes = window.prompt("Enter the ten passcodes from your most" +
-        " recent MFA SMS message (separated by spaces):", "").trim().split(" ");
+        " recent MFA SMS message (separated by spaces):", "")
+        .trim()
+        .split(" ")
+        .filter(passcode => passcode.match(/^\d+$/));
     if (passcodes.length != 10) {
         gebId("autoauth-message").innerHTML =
             "Invalid entry. Please try again.";

manifest.json

@@ -2,7 +2,7 @@
     "manifest_version": 2,
     "name": "AutoAuth for UCLA",
     "short_name": "AutoAuth",
-    "version": "0.5.1",
+    "version": "0.6",
     "description": "Speed up UCLA Single Sign-On.",
     "developer": {
       "name": "Kevin Hsieh",