diff --git a/Lantean.QBTMud/Helpers/DisplayHelpers.cs b/Lantean.QBTMud/Helpers/DisplayHelpers.cs
index c9c68fd..19d1753 100644
--- a/Lantean.QBTMud/Helpers/DisplayHelpers.cs
+++ b/Lantean.QBTMud/Helpers/DisplayHelpers.cs
@@ -19,28 +19,28 @@ namespace Lantean.QBTMud.Helpers
         {
             if (seconds is null)
             {
-                return "";
+                return string.Empty;
             }
 
-            if (seconds == 8640000)
+            const long InfiniteEtaSentinelSeconds = 8_640_000; // ~100 days, used by qBittorrent for "infinite" ETA.
+            var value = seconds.Value;
+
+            if (value >= long.MaxValue || value >= (long)TimeSpan.MaxValue.TotalSeconds || value == InfiniteEtaSentinelSeconds)
             {
                 return "∞";
             }
 
-            if (seconds < 60)
+            if (value <= 0)
             {
                 return "< 1m";
             }
 
-            TimeSpan time;
-            try
+            var time = TimeSpan.FromSeconds(value);
+            if (time.TotalMinutes < 1)
             {
-                time = TimeSpan.FromSeconds(seconds.Value);
-            }
-            catch
-            {
-                return "∞";
+                return "< 1m";
             }
+
             var sb = new StringBuilder();
             if (prefix is not null)
             {
@@ -83,6 +83,7 @@ namespace Lantean.QBTMud.Helpers
             return sb.ToString();
         }
 
+
         /// <summary>
         /// Formats a file size in bytes into an appropriate unit based on the size.
         /// </summary>
@@ -418,4 +419,4 @@ namespace Lantean.QBTMud.Helpers
             };
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Lantean.QBTMud/Helpers/FilterHelper.cs b/Lantean.QBTMud/Helpers/FilterHelper.cs
index 4c9f5e2..c5ab51e 100644
--- a/Lantean.QBTMud/Helpers/FilterHelper.cs
+++ b/Lantean.QBTMud/Helpers/FilterHelper.cs
@@ -119,34 +119,34 @@ namespace Lantean.QBTMud.Helpers
             switch (category)
             {
                 case CATEGORY_ALL:
-                    break;
+                    return true;
 
                 case CATEGORY_UNCATEGORIZED:
                     if (!string.IsNullOrEmpty(torrent.Category))
                     {
                         return false;
                     }
-                    break;
 
+                    return true;
                 default:
+                    if (string.IsNullOrEmpty(torrent.Category))
+                    {
+                        return false;
+                    }
+
                     if (!useSubcategories)
                     {
-                        if (torrent.Category != category)
-                        {
-                            return false;
-                        }
-                        else
-                        {
-                            if (!torrent.Category.StartsWith(category))
-                            {
-                                return false;
-                            }
-                        }
+                        return string.Equals(torrent.Category, category, StringComparison.Ordinal);
                     }
-                    break;
-            }
 
-            return true;
+                    if (string.Equals(torrent.Category, category, StringComparison.Ordinal))
+                    {
+                        return true;
+                    }
+
+                    var prefix = string.Concat(category, "/");
+                    return torrent.Category.StartsWith(prefix, StringComparison.Ordinal);
+            }
         }
 
         public static bool FilterTag(Torrent torrent, string tag)
@@ -284,4 +284,4 @@ namespace Lantean.QBTMud.Helpers
             };
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Lantean.QBTMud/Services/DataManager.cs b/Lantean.QBTMud/Services/DataManager.cs
index 7a5e8aa..3552331 100644
--- a/Lantean.QBTMud/Services/DataManager.cs
+++ b/Lantean.QBTMud/Services/DataManager.cs
@@ -39,12 +39,19 @@ namespace Lantean.QBTMud.Services
                 }
             }
 
-            var tags = new List<string>(mainData.Tags?.Count ?? 0);
+            var tags = new List<string>();
             if (mainData.Tags is not null)
             {
+                var seenTags = new HashSet<string>(StringComparer.Ordinal);
                 foreach (var tag in mainData.Tags)
                 {
-                    tags.Add(tag);
+                    var normalizedTag = NormalizeTag(tag);
+                    if (string.IsNullOrEmpty(normalizedTag) || !seenTags.Add(normalizedTag))
+                    {
+                        continue;
+                    }
+
+                    tags.Add(normalizedTag);
                 }
             }
 
@@ -157,8 +164,14 @@ namespace Lantean.QBTMud.Services
             {
                 foreach (var tag in mainData.TagsRemoved)
                 {
-                    torrentList.Tags.Remove(tag);
-                    torrentList.TagState.Remove(tag);
+                    var normalizedTag = NormalizeTag(tag);
+                    if (string.IsNullOrEmpty(normalizedTag))
+                    {
+                        continue;
+                    }
+
+                    torrentList.Tags.Remove(normalizedTag);
+                    torrentList.TagState.Remove(normalizedTag);
                 }
             }
 
@@ -200,7 +213,19 @@ namespace Lantean.QBTMud.Services
             {
                 foreach (var tag in mainData.Tags)
                 {
-                    torrentList.Tags.Add(tag);
+                    var normalizedTag = NormalizeTag(tag);
+                    if (string.IsNullOrEmpty(normalizedTag))
+                    {
+                        continue;
+                    }
+
+                    torrentList.Tags.Add(normalizedTag);
+                    if (!torrentList.TagState.ContainsKey(normalizedTag))
+                    {
+                        torrentList.TagState[normalizedTag] = torrentList.Torrents.Values
+                            .Where(t => FilterHelper.FilterTag(t, normalizedTag))
+                            .ToHashesHashSet();
+                    }
                 }
             }
 
@@ -508,6 +533,12 @@ namespace Lantean.QBTMud.Services
 
         public Torrent CreateTorrent(string hash, QBitTorrentClient.Models.Torrent torrent)
         {
+            var normalizedTags = torrent.Tags?
+                .Select(NormalizeTag)
+                .Where(static tag => !string.IsNullOrEmpty(tag))
+                .ToList()
+                ?? new List<string>();
+
             return new Torrent(
                 hash,
                 torrent.AddedOn.GetValueOrDefault(),
@@ -548,7 +579,7 @@ namespace Lantean.QBTMud.Services
                 torrent.Size.GetValueOrDefault(),
                 torrent.State!,
                 torrent.SuperSeeding.GetValueOrDefault(),
-                torrent.Tags!,
+                normalizedTags,
                 torrent.TimeActive.GetValueOrDefault(),
                 torrent.TotalSize.GetValueOrDefault(),
                 torrent.Tracker!,
@@ -561,6 +592,19 @@ namespace Lantean.QBTMud.Services
                 torrent.MaxInactiveSeedingTime.GetValueOrDefault());
         }
 
+        private static string NormalizeTag(string? tag)
+        {
+            if (string.IsNullOrEmpty(tag))
+            {
+                return string.Empty;
+            }
+
+            var separatorIndex = tag.IndexOf('\t');
+            var normalized = (separatorIndex >= 0) ? tag[..separatorIndex] : tag;
+
+            return normalized.Trim();
+        }
+
         private static void UpdateCategory(Category existingCategory, QBitTorrentClient.Models.Category category)
         {
             existingCategory.SavePath = category.SavePath ?? existingCategory.SavePath;
@@ -609,7 +653,14 @@ namespace Lantean.QBTMud.Services
             if (torrent.Tags is not null)
             {
                 existingTorrent.Tags.Clear();
-                existingTorrent.Tags.AddRange(torrent.Tags);
+                foreach (var tag in torrent.Tags)
+                {
+                    var normalizedTag = NormalizeTag(tag);
+                    if (!string.IsNullOrEmpty(normalizedTag))
+                    {
+                        existingTorrent.Tags.Add(normalizedTag);
+                    }
+                }
             }
             existingTorrent.TimeActive = torrent.TimeActive ?? existingTorrent.TimeActive;
             existingTorrent.TotalSize = torrent.TotalSize ?? existingTorrent.TotalSize;
@@ -1175,4 +1226,4 @@ namespace Lantean.QBTMud.Services
             return new RssList(feeds, articles);
         }
     }
-}
\ No newline at end of file
+}