Fix a maddeningly subtle URL parsing bug

docs/index.html

@@ -9,7 +9,7 @@
 
     <link rel="icon" type="image/svg+xml" href="/fivel/favicon.svg" />
     <link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
-  <script type="module" crossorigin src="/fivel/assets/index-Tcjc4s4K.js"></script>
+  <script type="module" crossorigin src="/fivel/assets/index-CzsmwQDA.js"></script>
   <link rel="stylesheet" crossorigin href="/fivel/assets/index-BwGB0A6o.css">
 </head>
 

src/stores.ts

@@ -97,8 +97,14 @@ const _createKeyColors = () => {
     };
 };
 
-const _urlParams = new URLSearchParams(window.location.search);
-const _serializedGameConfig = _urlParams.get("f");
+// Using URLSearchParams might seem easier than manually parsing this URL. Unfortunately, URLSearchParams parses the
+// URL, and that includes decoding values. If our Base64 includes a "+", this is bad news. That plus will be decoded as
+// a space. That is *not* valid Base64 and will break when passed into GameConfig.deserialize().
+let _serializedGameConfig: string | null = null;
+if (location.search.length > 3) {
+    // Trim the "?f=" from our search
+    _serializedGameConfig = location.search.substring(3);
+}
 
 export const guesses = _createGuesses();
 export const guessesAreExhausted = derived(guesses, $guesses => $guesses.every(guess => guess.isSubmitted));

src/util/GameConfig.ts

@@ -18,7 +18,8 @@ export default class GameConfig {
 
     static deserialize(s: string) {
         const binaryString = atob(s);
-        const bytes = Uint8Array.from(binaryString, (m) => m.codePointAt(0) ?? 0);
+        // 32 represents the space character in UTF-8
+        const bytes = Uint8Array.from(binaryString, (m) => m.codePointAt(0) ?? 32);
         const jsonString = new TextDecoder().decode(bytes);
         const json = JSON.parse(jsonString);
         return new GameConfig(json.word, json.gameId, json.hint);