Persist quick send history safely

lib/main.dart

@@ -221,7 +221,7 @@ class _InputSyncPageState extends State<InputSyncPage>
   @override
   void didChangeAppLifecycleState(AppLifecycleState state) {
     if (state == AppLifecycleState.resumed) {
-      unawaited(_syncAppendEnterFromPrefs());
+      unawaited(_syncSharedPrefsFromDisk());
     }
   }
 
@@ -239,7 +239,7 @@ class _InputSyncPageState extends State<InputSyncPage>
           prefs.getString(_portKey) ?? nativeState.port.toString();
       clearAfterSend = prefs.getBool(_clearAfterSendKey) ?? false;
       appendEnter = prefs.getBool(_appendEnterKey) ?? false;
-      sendHistory = prefs.getStringList(_historyKey) ?? [];
+      sendHistory = _readHistory(prefs);
       connection = nativeState;
       headerExpanded = !nativeState.connected;
     });
@@ -459,17 +459,44 @@ class _InputSyncPageState extends State<InputSyncPage>
     });
   }
 
-  Future<void> _syncAppendEnterFromPrefs() async {
+  Future<void> _syncSharedPrefsFromDisk() async {
     final prefs = await SharedPreferences.getInstance();
     await prefs.reload();
     final nextAppendEnter = prefs.getBool(_appendEnterKey) ?? false;
-    if (!mounted || nextAppendEnter == appendEnter) {
+    final nextHistory = _readHistory(prefs);
+    if (!mounted) {
       return;
     }
 
-    setState(() {
-      appendEnter = nextAppendEnter;
-    });
+    if (nextAppendEnter != appendEnter ||
+        !_stringListsEqual(nextHistory, sendHistory)) {
+      setState(() {
+        appendEnter = nextAppendEnter;
+        sendHistory = nextHistory;
+      });
+    }
+  }
+
+  bool _stringListsEqual(List<String> left, List<String> right) {
+    if (left.length != right.length) {
+      return false;
+    }
+
+    for (var index = 0; index < left.length; index += 1) {
+      if (left[index] != right[index]) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+  List<String> _readHistory(SharedPreferences prefs) {
+    try {
+      return prefs.getStringList(_historyKey) ?? [];
+    } catch (_) {
+      return [];
+    }
   }
 
   void _restoreHistory(String text) {