diff --git a/HellionChat/SelfTests/HoverStateFootprintStep.cs b/HellionChat/SelfTests/HoverStateFootprintStep.cs
index e726155..a8c9d43 100644
--- a/HellionChat/SelfTests/HoverStateFootprintStep.cs
+++ b/HellionChat/SelfTests/HoverStateFootprintStep.cs
@@ -59,13 +59,36 @@ internal sealed class HoverStateFootprintStep : ISelfTestStep
 
             if (HoverState.TrackedCount != 0)
             {
-                var msg = $"Registry leaked {HoverState.TrackedCount} entries after fade-out";
-                ImGui.Text(msg);
-                SelfTestReport.Append(Name, "FAIL", new[] { msg });
+                var leak = $"Registry leaked {HoverState.TrackedCount} entries after fade-out";
+                ImGui.Text(leak);
+                SelfTestReport.Append(Name, "FAIL", new[] { leak });
                 return SelfTestStepResult.Fail;
             }
 
-            SelfTestReport.Append(Name, "PASS", new[] { "registry empty after fade-out" });
+            // The case a hovered-only probe cannot see: querying an element that
+            // is NOT hovered must not create an entry. Otherwise every row in
+            // the window allocates one per frame and loses it again in the next
+            // BeginFrame, forever.
+            for (var frame = 0; frame < 10; frame++)
+            {
+                foreach (var id in ids)
+                    HoverState.Query(id, hovered: false);
+                HoverState.AdvanceForTest(Frame);
+
+                if (HoverState.TrackedCount == 0)
+                    continue;
+
+                var churn = $"Unhovered query created {HoverState.TrackedCount} entries";
+                ImGui.Text(churn);
+                SelfTestReport.Append(Name, "FAIL", new[] { churn });
+                return SelfTestStepResult.Fail;
+            }
+
+            SelfTestReport.Append(
+                Name,
+                "PASS",
+                new[] { "no growth while hovered, empty after fade-out, no churn when idle" }
+            );
             return SelfTestStepResult.Pass;
         }
         finally
diff --git a/HellionChat/Ui/StyleEngine/HoverState.cs b/HellionChat/Ui/StyleEngine/HoverState.cs
index f3d194e..15775ad 100644
--- a/HellionChat/Ui/StyleEngine/HoverState.cs
+++ b/HellionChat/Ui/StyleEngine/HoverState.cs
@@ -48,6 +48,12 @@ internal static class HoverState
 
         if (!Entries.TryGetValue(id, out var entry))
         {
+            // Nothing to fade from, so nothing to track. Without this a
+            // never-hovered element allocates an entry in Query and loses it
+            // again in the next BeginFrame, every frame, for every row.
+            if (!hovered)
+                return 0f;
+
             entry = new Entry();
             Entries[id] = entry;
         }
@@ -58,10 +64,19 @@ internal static class HoverState
         return entry.Value;
     }
 
+    // Never re-entrant: BeginFrame runs once from the draw thread, AdvanceForTest
+    // only from a self-test step. Evicted is shared, so overlapping calls would
+    // corrupt it.
     private static void Advance(float deltaTime)
     {
         if (deltaTime <= 0f)
+        {
+            // Still clear the flags: a zero-delta frame otherwise carries the
+            // previous frame's hover state forward.
+            foreach (var entry in Entries.Values)
+                entry.Hovered = false;
             return;
+        }
 
         Evicted.Clear();
         foreach (var (id, entry) in Entries)
diff --git a/HellionChat/Ui/StyleEngine/Metrics.cs b/HellionChat/Ui/StyleEngine/Metrics.cs
index 849d45c..5a1ef30 100644
--- a/HellionChat/Ui/StyleEngine/Metrics.cs
+++ b/HellionChat/Ui/StyleEngine/Metrics.cs
@@ -66,8 +66,10 @@ internal static class Metrics
             if (frame == _cachedFrame)
                 return _cachedScale;
 
+            // Safe variant: GlobalScale throws while the interface manager is
+            // still coming up, and Block F pulls Metrics into more call sites.
+            _cachedScale = ImGuiHelpers.GlobalScaleSafe;
             _cachedFrame = frame;
-            _cachedScale = ImGuiHelpers.GlobalScale;
             return _cachedScale;
         }
     }
diff --git a/HellionChat/Ui/StyleEngine/Widgets/Badge.cs b/HellionChat/Ui/StyleEngine/Widgets/Badge.cs
index 44f29cb..a639201 100644
--- a/HellionChat/Ui/StyleEngine/Widgets/Badge.cs
+++ b/HellionChat/Ui/StyleEngine/Widgets/Badge.cs
@@ -21,8 +21,14 @@ internal static class Badge
     internal static string Format(int count, int maxCount) =>
         count > maxCount ? $"{maxCount}+" : count.ToString();
 
+    // Zero for a count of zero, matching Draw: a caller that reserves space and
+    // then draws would otherwise leave a badge-shaped hole on every tab without
+    // unread messages, which is the normal case.
     internal static Vector2 CalcSize(int count, BadgeStyle? styleOverride = null)
     {
+        if (count <= 0)
+            return Vector2.Zero;
+
         var style = styleOverride ?? new BadgeStyle();
         var text = Format(count, style.MaxCount);
         return WidgetGeometry.Badge(
diff --git a/HellionChat/Ui/StyleEngine/Widgets/IconButton.cs b/HellionChat/Ui/StyleEngine/Widgets/IconButton.cs
index 488c5e9..2bd23b8 100644
--- a/HellionChat/Ui/StyleEngine/Widgets/IconButton.cs
+++ b/HellionChat/Ui/StyleEngine/Widgets/IconButton.cs
@@ -20,9 +20,23 @@ internal readonly record struct IconButtonStyle
 // the hit area plus the glyph.
 internal static class IconButton
 {
+    // FontAwesomeExtensions.ToIconString allocates on every call and holds no
+    // cache of its own, so a per-frame glyph would allocate per button per frame.
+    private static readonly Dictionary<FontAwesomeIcon, string> GlyphCache = [];
+
     internal static Vector2 CalcSize(float width, float height) =>
         WidgetGeometry.IconButton(width, height);
 
+    private static string Glyph(FontAwesomeIcon icon)
+    {
+        if (GlyphCache.TryGetValue(icon, out var s))
+            return s;
+
+        s = icon.ToIconString();
+        GlyphCache[icon] = s;
+        return s;
+    }
+
     internal static (bool Clicked, bool Hovered) Draw(
         uint id,
         Vector2 size,
@@ -59,7 +73,7 @@ internal static class IconButton
         {
             using (font.Push())
             {
-                var text = icon.ToIconString();
+                var text = Glyph(icon);
                 var textSize = ImGui.CalcTextSize(text);
                 dl.AddText(origin + (clamped - textSize) * 0.5f, glyphAbgr, text);
             }
diff --git a/HellionChat/Ui/Windows/WidgetGalleryWindow.cs b/HellionChat/Ui/Windows/WidgetGalleryWindow.cs
index ba17a31..3663d4e 100644
--- a/HellionChat/Ui/Windows/WidgetGalleryWindow.cs
+++ b/HellionChat/Ui/Windows/WidgetGalleryWindow.cs
@@ -55,8 +55,14 @@ internal sealed class WidgetGalleryWindow : Window
         ImGui.TextUnformatted("Row");
         ImGui.Checkbox("active##row", ref _rowActive);
 
-        var width = ImGui.GetContentRegionAvail().X;
-        var height = Metrics.SidebarRowHeight;
+        // Clamped: this window demonstrates the guard, it should not be the one
+        // that asserts when dragged narrow.
+        var rowSize = HellionChat.Util.WidgetGeometry.IconButton(
+            ImGui.GetContentRegionAvail().X,
+            Metrics.SidebarRowHeight
+        );
+        var width = rowSize.X;
+        var height = rowSize.Y;
 
         for (var i = 0; i < 3; i++)
         {