TF-4171 Display tag in mailbox list

core/lib/presentation/extensions/hex_color_extension.dart

@@ -0,0 +1,18 @@
+import 'package:flutter/material.dart';
+
+extension HexColorExtension on String {
+  Color toColor({Color fallback = Colors.transparent}) {
+    try {
+      final hex = replaceAll('#', '');
+
+      if (hex.length != 6 && hex.length != 8) {
+        return fallback;
+      }
+
+      final fullHex = hex.length == 6 ? 'FF$hex' : hex;
+      return Color(int.parse(fullHex, radix: 16));
+    } catch (_) {
+      return fallback;
+    }
+  }
+}