diff --git a/src/Avalonia.Base/Media/TextFormatting/SplitResult.cs b/src/Avalonia.Base/Media/TextFormatting/SplitResult.cs
index 53021c4656..c1ac57ce46 100644
--- a/src/Avalonia.Base/Media/TextFormatting/SplitResult.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/SplitResult.cs
@@ -26,5 +26,16 @@
         /// The second part.
         /// </value>
         public T? Second { get; }
+
+        /// <summary>
+        /// Deconstructs the split results into its components.
+        /// </summary>
+        /// <param name="first">On return, contains the first part.</param>
+        /// <param name="second">On return, contains the second part.</param>
+        public void Deconstruct(out T first, out T? second)
+        {
+            first = First;
+            second = Second;
+        }
     }
 }
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextCharacters.cs b/src/Avalonia.Base/Media/TextFormatting/TextCharacters.cs
index 2525f0dbf9..6454f9bfa3 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextCharacters.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextCharacters.cs
@@ -46,24 +46,21 @@ namespace Avalonia.Media.TextFormatting
         /// Gets a list of <see cref="UnshapedTextRun"/>.
         /// </summary>
         /// <returns>The shapeable text characters.</returns>
-        internal IReadOnlyList<UnshapedTextRun> GetShapeableCharacters(ReadOnlyMemory<char> text, sbyte biDiLevel,
-            ref TextRunProperties? previousProperties)
+        internal void GetShapeableCharacters(ReadOnlyMemory<char> text, sbyte biDiLevel,
+            ref TextRunProperties? previousProperties, List<TextRun> results)
         {
-            var shapeableCharacters = new List<UnshapedTextRun>(2);
             var properties = Properties;
 
             while (!text.IsEmpty)
             {
                 var shapeableRun = CreateShapeableRun(text, properties, biDiLevel, ref previousProperties);
 
-                shapeableCharacters.Add(shapeableRun);
+                results.Add(shapeableRun);
 
                 text = text.Slice(shapeableRun.Length);
 
                 previousProperties = shapeableRun.Properties;
             }
-
-            return shapeableCharacters;
         }
 
         /// <summary>
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextCollapsingProperties.cs b/src/Avalonia.Base/Media/TextFormatting/TextCollapsingProperties.cs
index 01804e1ce3..72882df0b5 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextCollapsingProperties.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextCollapsingProperties.cs
@@ -1,6 +1,4 @@
-using System.Collections.Generic;
-
-namespace Avalonia.Media.TextFormatting
+namespace Avalonia.Media.TextFormatting
 {
     /// <summary>
     /// Properties of text collapsing.
@@ -21,6 +19,6 @@ namespace Avalonia.Media.TextFormatting
         /// Collapses given text line.
         /// </summary>
         /// <param name="textLine">Text line to collapse.</param>
-        public abstract List<TextRun>? Collapse(TextLine textLine);
+        public abstract TextRun[]? Collapse(TextLine textLine);
     }
 }
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextEllipsisHelper.cs b/src/Avalonia.Base/Media/TextFormatting/TextEllipsisHelper.cs
index 528cd45581..97f8b2483b 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextEllipsisHelper.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextEllipsisHelper.cs
@@ -1,15 +1,18 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
+using System.Linq;
 using Avalonia.Media.TextFormatting.Unicode;
+using Avalonia.Utilities;
 
 namespace Avalonia.Media.TextFormatting
 {
     internal static class TextEllipsisHelper
     {
-        public static List<TextRun>? Collapse(TextLine textLine, TextCollapsingProperties properties, bool isWordEllipsis)
+        public static TextRun[]? Collapse(TextLine textLine, TextCollapsingProperties properties, bool isWordEllipsis)
         {
             var textRuns = textLine.TextRuns;
 
-            if (textRuns == null || textRuns.Count == 0)
+            if (textRuns.Count == 0)
             {
                 return null;
             }
@@ -22,7 +25,7 @@ namespace Avalonia.Media.TextFormatting
             if (properties.Width < shapedSymbol.GlyphRun.Size.Width)
             {
                 //Not enough space to fit in the symbol
-                return new List<TextRun>(0);
+                return Array.Empty<TextRun>();
             }
 
             var availableWidth = properties.Width - shapedSymbol.Size.Width;
@@ -70,18 +73,7 @@ namespace Avalonia.Media.TextFormatting
 
                                 collapsedLength += measuredLength;
 
-                                var collapsedRuns = new List<TextRun>(textRuns.Count);
-
-                                if (collapsedLength > 0)
-                                {
-                                    var splitResult = TextFormatterImpl.SplitTextRuns(textRuns, collapsedLength);
-
-                                    collapsedRuns.AddRange(splitResult.First);
-                                }
-
-                                collapsedRuns.Add(shapedSymbol);
-
-                                return collapsedRuns;
+                                return CreateCollapsedRuns(textRuns, collapsedLength, shapedSymbol);
                             }
 
                             availableWidth -= shapedRun.Size.Width;
@@ -94,18 +86,7 @@ namespace Avalonia.Media.TextFormatting
                             //The whole run needs to fit into available space
                             if (currentWidth + drawableRun.Size.Width > availableWidth)
                             {
-                                var collapsedRuns = new List<TextRun>(textRuns.Count);
-
-                                if (collapsedLength > 0)
-                                {
-                                    var splitResult = TextFormatterImpl.SplitTextRuns(textRuns, collapsedLength);
-
-                                    collapsedRuns.AddRange(splitResult.First);
-                                }
-
-                                collapsedRuns.Add(shapedSymbol);
-
-                                return collapsedRuns;
+                                return CreateCollapsedRuns(textRuns, collapsedLength, shapedSymbol);
                             }
 
                             availableWidth -= drawableRun.Size.Width;
@@ -121,5 +102,30 @@ namespace Avalonia.Media.TextFormatting
 
             return null;
         }
+
+        private static TextRun[] CreateCollapsedRuns(IReadOnlyList<TextRun> textRuns, int collapsedLength,
+            TextRun shapedSymbol)
+        {
+            if (collapsedLength <= 0)
+            {
+                return new[] { shapedSymbol };
+            }
+
+            // perf note: the runs are very likely to come from TextLineImpl
+            // which already uses an array: ToArray() won't ever be called in this case
+            var textRunArray = textRuns as TextRun[] ?? textRuns.ToArray();
+
+            var (preSplitRuns, _) = TextFormatterImpl.SplitTextRuns(textRunArray, collapsedLength);
+
+            var collapsedRuns = new TextRun[preSplitRuns.Count + 1];
+
+            for (var i = 0; i < preSplitRuns.Count; ++i)
+            {
+                collapsedRuns[i] = preSplitRuns[i];
+            }
+
+            collapsedRuns[collapsedRuns.Length - 1] = shapedSymbol;
+            return collapsedRuns;
+        }
     }
 }
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextFormatterImpl.cs b/src/Avalonia.Base/Media/TextFormatting/TextFormatterImpl.cs
index 8afecb09e2..5c073452f4 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextFormatterImpl.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextFormatterImpl.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Buffers;
 using System.Collections.Generic;
+using System.Linq;
 using System.Runtime.InteropServices;
 using Avalonia.Media.TextFormatting.Unicode;
 using Avalonia.Utilities;
@@ -23,10 +24,10 @@ namespace Avalonia.Media.TextFormatting
             var fetchedRuns = FetchTextRuns(textSource, firstTextSourceIndex,
                 out var textEndOfLine, out var textSourceLength);
 
-            if (previousLineBreak?.RemainingRuns != null)
+            if (previousLineBreak?.RemainingRuns is { } remainingRuns)
             {
                 resolvedFlowDirection = previousLineBreak.FlowDirection;
-                textRuns = previousLineBreak.RemainingRuns;
+                textRuns = remainingRuns;
                 nextLineBreak = previousLineBreak;
             }
             else
@@ -45,7 +46,7 @@ namespace Avalonia.Media.TextFormatting
             {
                 case TextWrapping.NoWrap:
                     {
-                        textLine = new TextLineImpl(textRuns, firstTextSourceIndex, textSourceLength,
+                        textLine = new TextLineImpl(textRuns.ToArray(), firstTextSourceIndex, textSourceLength,
                             paragraphWidth, paragraphProperties, resolvedFlowDirection, nextLineBreak);
 
                         textLine.FinalizeLine();
@@ -160,6 +161,14 @@ namespace Avalonia.Media.TextFormatting
         {
             var flowDirection = paragraphProperties.FlowDirection;
             var shapedRuns = new List<TextRun>();
+
+            if (textRuns.Count == 0)
+            {
+                resolvedFlowDirection = flowDirection;
+                return shapedRuns;
+            }
+
+
             using var biDiData = new BidiData((sbyte)flowDirection);
 
             foreach (var textRun in textRuns)
@@ -224,7 +233,7 @@ namespace Avalonia.Media.TextFormatting
                                          shapeableRun.BidiLevel, currentRun.Properties.CultureInfo,
                                          paragraphProperties.DefaultIncrementalTab, paragraphProperties.LetterSpacing);
 
-                            shapedRuns.AddRange(ShapeTogether(groupedRuns, text, shaperOptions));
+                            ShapeTogether(groupedRuns, text, shaperOptions, shapedRuns);
 
                             break;
                         }
@@ -309,11 +318,9 @@ namespace Avalonia.Media.TextFormatting
                && x.Typeface == y.Typeface
                && x.BaselineAlignment == y.BaselineAlignment;
 
-        private static IReadOnlyList<ShapedTextRun> ShapeTogether(
-            IReadOnlyList<UnshapedTextRun> textRuns, ReadOnlyMemory<char> text, TextShaperOptions options)
+        private static void ShapeTogether(IReadOnlyList<UnshapedTextRun> textRuns, ReadOnlyMemory<char> text,
+            TextShaperOptions options, List<TextRun> results)
         {
-            var shapedRuns = new List<ShapedTextRun>(textRuns.Count);
-
             var shapedBuffer = TextShaper.Current.ShapeText(text, options);
 
             for (var i = 0; i < textRuns.Count; i++)
@@ -322,12 +329,10 @@ namespace Avalonia.Media.TextFormatting
 
                 var splitResult = shapedBuffer.Split(currentRun.Length);
 
-                shapedRuns.Add(new ShapedTextRun(splitResult.First, currentRun.Properties));
+                results.Add(new ShapedTextRun(splitResult.First, currentRun.Properties));
 
                 shapedBuffer = splitResult.Second!;
             }
-
-            return shapedRuns;
         }
 
         /// <summary>
@@ -335,7 +340,7 @@ namespace Avalonia.Media.TextFormatting
         /// </summary>
         /// <param name="textCharacters">The text characters to form <see cref="UnshapedTextRun"/> from.</param>
         /// <param name="levels">The bidi levels.</param>
-        /// <param name="processedRuns"></param>
+        /// <param name="processedRuns">A list that will be filled with the processed runs.</param>
         /// <returns></returns>
         private static void CoalesceLevels(IReadOnlyList<TextRun> textCharacters, ArraySlice<sbyte> levels,
             List<TextRun> processedRuns)
@@ -385,7 +390,8 @@ namespace Avalonia.Media.TextFormatting
 
                     if (j == runTextSpan.Length)
                     {
-                        processedRuns.AddRange(currentRun.GetShapeableCharacters(runText.Slice(0, j), runLevel, ref previousProperties));
+                        currentRun.GetShapeableCharacters(runText.Slice(0, j), runLevel, ref previousProperties,
+                            processedRuns);
 
                         runLevel = levels[levelIndex];
 
@@ -398,7 +404,8 @@ namespace Avalonia.Media.TextFormatting
                     }
 
                     // End of this run
-                    processedRuns.AddRange(currentRun.GetShapeableCharacters(runText.Slice(0, j), runLevel, ref previousProperties));
+                    currentRun.GetShapeableCharacters(runText.Slice(0, j), runLevel, ref previousProperties,
+                        processedRuns);
 
                     runText = runText.Slice(j);
                     runTextSpan = runText.Span;
@@ -415,7 +422,7 @@ namespace Avalonia.Media.TextFormatting
                 return;
             }
 
-            processedRuns.AddRange(currentRun.GetShapeableCharacters(runText, runLevel, ref previousProperties));
+            currentRun.GetShapeableCharacters(runText, runLevel, ref previousProperties, processedRuns);
         }
 
         /// <summary>
@@ -423,8 +430,8 @@ namespace Avalonia.Media.TextFormatting
         /// </summary>
         /// <param name="textSource">The text source.</param>
         /// <param name="firstTextSourceIndex">The first text source index.</param>
-        /// <param name="endOfLine"></param>
-        /// <param name="textSourceLength"></param>
+        /// <param name="endOfLine">On return, the end of line, if any.</param>
+        /// <param name="textSourceLength">On return, the processed text source length.</param>
         /// <returns>
         /// The formatted text runs.
         /// </returns>
@@ -602,7 +609,7 @@ namespace Avalonia.Media.TextFormatting
             var shapedBuffer = new ShapedBuffer(s_empty.AsMemory(), glyphInfos, glyphTypeface, properties.FontRenderingEmSize,
                 (sbyte)flowDirection);
 
-            var textRuns = new List<DrawableTextRun> { new ShapedTextRun(shapedBuffer, properties) };
+            var textRuns = new TextRun[] { new ShapedTextRun(shapedBuffer, properties) };
 
             return new TextLineImpl(textRuns, firstTextSourceIndex, 0, paragraphWidth, paragraphProperties, flowDirection).FinalizeLine();
         }
@@ -749,12 +756,10 @@ namespace Avalonia.Media.TextFormatting
                 break;
             }
 
-            var splitResult = SplitTextRuns(textRuns, measuredLength);
-
-            var remainingCharacters = splitResult.Second;
+            var (preSplitRuns, postSplitRuns) = SplitTextRuns(textRuns, measuredLength);
 
-            var lineBreak = remainingCharacters?.Count > 0 ?
-                new TextLineBreak(null, resolvedFlowDirection, remainingCharacters) :
+            var lineBreak = postSplitRuns?.Count > 0 ?
+                new TextLineBreak(null, resolvedFlowDirection, postSplitRuns) :
                 null;
 
             if (lineBreak is null && currentLineBreak?.TextEndOfLine != null)
@@ -762,7 +767,7 @@ namespace Avalonia.Media.TextFormatting
                 lineBreak = new TextLineBreak(currentLineBreak.TextEndOfLine, resolvedFlowDirection);
             }
 
-            var textLine = new TextLineImpl(splitResult.First, firstTextSourceIndex, measuredLength,
+            var textLine = new TextLineImpl(preSplitRuns.ToArray(), firstTextSourceIndex, measuredLength,
                 paragraphWidth, paragraphProperties, resolvedFlowDirection,
                 lineBreak);
 
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextLayout.cs b/src/Avalonia.Base/Media/TextFormatting/TextLayout.cs
index 468623b356..55b6f14267 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextLayout.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextLayout.cs
@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using Avalonia.Utilities;
 
 namespace Avalonia.Media.TextFormatting
@@ -13,6 +12,7 @@ namespace Avalonia.Media.TextFormatting
         private readonly ITextSource _textSource;
         private readonly TextParagraphProperties _paragraphProperties;
         private readonly TextTrimming _textTrimming;
+        private readonly TextLine[] _textLines;
 
         private int _textSourceLength;
 
@@ -69,7 +69,7 @@ namespace Avalonia.Media.TextFormatting
 
             MaxLines = maxLines;
 
-            TextLines = CreateTextLines();
+            _textLines = CreateTextLines();
         }
 
         /// <summary>
@@ -109,7 +109,7 @@ namespace Avalonia.Media.TextFormatting
 
             MaxLines = maxLines;
 
-            TextLines = CreateTextLines();
+            _textLines = CreateTextLines();
         }
 
         /// <summary>
@@ -147,7 +147,8 @@ namespace Avalonia.Media.TextFormatting
         /// <value>
         /// The text lines.
         /// </value>
-        public IReadOnlyList<TextLine> TextLines { get; private set; }
+        public IReadOnlyList<TextLine> TextLines
+            => _textLines;
 
         /// <summary>
         /// Gets the bounds of the layout.
@@ -164,14 +165,14 @@ namespace Avalonia.Media.TextFormatting
         /// <param name="origin">The origin.</param>
         public void Draw(DrawingContext context, Point origin)
         {
-            if (!TextLines.Any())
+            if (_textLines.Length == 0)
             {
                 return;
             }
 
             var (currentX, currentY) = origin;
 
-            foreach (var textLine in TextLines)
+            foreach (var textLine in _textLines)
             {
                 textLine.Draw(context, new Point(currentX + textLine.Start, currentY));
 
@@ -186,7 +187,7 @@ namespace Avalonia.Media.TextFormatting
         /// <returns></returns>
         public Rect HitTestTextPosition(int textPosition)
         {
-            if (TextLines.Count == 0)
+            if (_textLines.Length == 0)
             {
                 return new Rect();
             }
@@ -198,7 +199,7 @@ namespace Avalonia.Media.TextFormatting
 
             var currentY = 0.0;
 
-            foreach (var textLine in TextLines)
+            foreach (var textLine in _textLines)
             {
                 var end = textLine.FirstTextSourceIndex + textLine.Length;
 
@@ -230,11 +231,11 @@ namespace Avalonia.Media.TextFormatting
                 return Array.Empty<Rect>();
             }
 
-            var result = new List<Rect>(TextLines.Count);
+            var result = new List<Rect>(_textLines.Length);
 
             var currentY = 0d;
 
-            foreach (var textLine in TextLines)
+            foreach (var textLine in _textLines)
             {
                 //Current line isn't covered.
                 if (textLine.FirstTextSourceIndex + textLine.Length < start)
@@ -284,13 +285,12 @@ namespace Avalonia.Media.TextFormatting
         {
             var currentY = 0d;
 
-            var lineIndex = 0;
             TextLine? currentLine = null;
             CharacterHit characterHit;
 
-            for (; lineIndex < TextLines.Count; lineIndex++)
+            for (var lineIndex = 0; lineIndex < _textLines.Length; lineIndex++)
             {
-                currentLine = TextLines[lineIndex];
+                currentLine = _textLines[lineIndex];
 
                 if (currentY + currentLine.Height > point.Y)
                 {
@@ -322,12 +322,12 @@ namespace Avalonia.Media.TextFormatting
 
             if (charIndex > _textSourceLength)
             {
-                return TextLines.Count - 1;
+                return _textLines.Length - 1;
             }
 
-            for (var index = 0; index < TextLines.Count; index++)
+            for (var index = 0; index < _textLines.Length; index++)
             {
-                var textLine = TextLines[index];
+                var textLine = _textLines[index];
 
                 if (textLine.FirstTextSourceIndex + textLine.Length < charIndex)
                 {
@@ -341,7 +341,7 @@ namespace Avalonia.Media.TextFormatting
                 }
             }
 
-            return TextLines.Count - 1;
+            return _textLines.Length - 1;
         }
 
         private TextHitTestResult GetHitTestResult(TextLine textLine, CharacterHit characterHit, Point point)
@@ -424,7 +424,7 @@ namespace Avalonia.Media.TextFormatting
             height += textLine.Height;
         }
 
-        private IReadOnlyList<TextLine> CreateTextLines()
+        private TextLine[] CreateTextLines()
         {
             if (MathUtilities.IsZero(MaxWidth) || MathUtilities.IsZero(MaxHeight))
             {
@@ -432,7 +432,7 @@ namespace Avalonia.Media.TextFormatting
 
                 Bounds = new Rect(0, 0, 0, textLine.Height);
 
-                return new List<TextLine> { textLine };
+                return new TextLine[] { textLine };
             }
 
             var textLines = new List<TextLine>();
@@ -443,12 +443,14 @@ namespace Avalonia.Media.TextFormatting
 
             TextLine? previousLine = null;
 
+            var textFormatter = TextFormatter.Current;
+
             while (true)
             {
-                var textLine = TextFormatter.Current.FormatLine(_textSource, _textSourceLength, MaxWidth,
+                var textLine = textFormatter.FormatLine(_textSource, _textSourceLength, MaxWidth,
                     _paragraphProperties, previousLine?.TextLineBreak);
 
-                if(textLine == null || textLine.Length == 0)
+                if (textLine.Length == 0)
                 {
                     if (previousLine != null && previousLine.NewLineLength > 0)
                     {
@@ -524,8 +526,9 @@ namespace Avalonia.Media.TextFormatting
             {
                 var whitespaceWidth = 0d;
 
-                foreach (var line in textLines)
+                for (var i = 0; i < textLines.Count; i++)
                 {
+                    var line = textLines[i];
                     var lineWhitespaceWidth = line.Width - line.WidthIncludingTrailingWhitespace;
 
                     if (lineWhitespaceWidth > whitespaceWidth)
@@ -549,7 +552,7 @@ namespace Avalonia.Media.TextFormatting
                 }
             }
 
-            return textLines;
+            return textLines.ToArray();
         }
 
         /// <summary>
@@ -569,7 +572,7 @@ namespace Avalonia.Media.TextFormatting
 
         public void Dispose()
         {
-            foreach (var line in TextLines)
+            foreach (var line in _textLines)
             {
                 line.Dispose();
             }
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextLeadingPrefixCharacterEllipsis.cs b/src/Avalonia.Base/Media/TextFormatting/TextLeadingPrefixCharacterEllipsis.cs
index e30a0fe9f4..672a15b398 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextLeadingPrefixCharacterEllipsis.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextLeadingPrefixCharacterEllipsis.cs
@@ -1,5 +1,7 @@
-using System;
+// ReSharper disable ForCanBeConvertedToForeach
+using System;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace Avalonia.Media.TextFormatting
 {
@@ -39,11 +41,12 @@ namespace Avalonia.Media.TextFormatting
         /// <inheritdoc/>
         public override TextRun Symbol { get; }
 
-        public override List<TextRun>? Collapse(TextLine textLine)
+        /// <inheritdoc />
+        public override TextRun[]? Collapse(TextLine textLine)
         {
             var textRuns = textLine.TextRuns;
 
-            if (textRuns == null || textRuns.Count == 0)
+            if (textRuns.Count == 0)
             {
                 return null;
             }
@@ -54,7 +57,7 @@ namespace Avalonia.Media.TextFormatting
 
             if (Width < shapedSymbol.GlyphRun.Size.Width)
             {
-                return new List<TextRun>(0);
+                return Array.Empty<TextRun>();
             }
 
             // Overview of ellipsis structure
@@ -75,41 +78,48 @@ namespace Avalonia.Media.TextFormatting
                             {
                                 shapedRun.TryMeasureCharacters(availableWidth, out var measuredLength);
 
-                                var collapsedRuns = new List<TextRun>(textRuns.Count);
-
                                 if (measuredLength > 0)
                                 {
-                                    IReadOnlyList<TextRun>? preSplitRuns = null;
+                                    var collapsedRuns = new List<TextRun>(textRuns.Count + 1);
+
+                                    // perf note: the runs are very likely to come from TextLineImpl,
+                                    // which already uses an array: ToArray() won't ever be called in this case
+                                    var textRunArray = textRuns as TextRun[] ?? textRuns.ToArray();
+
+                                    IReadOnlyList<TextRun>? preSplitRuns;
                                     IReadOnlyList<TextRun>? postSplitRuns;
 
                                     if (_prefixLength > 0)
                                     {
-                                        var splitResult = TextFormatterImpl.SplitTextRuns(textRuns,
-                                            Math.Min(_prefixLength, measuredLength));
+                                        (preSplitRuns, postSplitRuns) = TextFormatterImpl.SplitTextRuns(
+                                            textRunArray, Math.Min(_prefixLength, measuredLength));
 
-                                        collapsedRuns.AddRange(splitResult.First);
-
-                                        preSplitRuns = splitResult.First;
-                                        postSplitRuns = splitResult.Second;
+                                        for (var i = 0; i < preSplitRuns.Count; i++)
+                                        {
+                                            var preSplitRun = preSplitRuns[i];
+                                            collapsedRuns.Add(preSplitRun);
+                                        }
                                     }
                                     else
                                     {
-                                        postSplitRuns = textRuns;
+                                        preSplitRuns = null;
+                                        postSplitRuns = textRunArray;
                                     }
 
                                     collapsedRuns.Add(shapedSymbol);
 
                                     if (measuredLength <= _prefixLength || postSplitRuns is null)
                                     {
-                                        return collapsedRuns;
+                                        return collapsedRuns.ToArray();
                                     }
 
                                     var availableSuffixWidth = availableWidth;
 
                                     if (preSplitRuns is not null)
                                     {
-                                        foreach (var run in preSplitRuns)
+                                        for (var i = 0; i < preSplitRuns.Count; i++)
                                         {
+                                            var run = preSplitRuns[i];
                                             if (run is DrawableTextRun drawableTextRun)
                                             {
                                                 availableSuffixWidth -= drawableTextRun.Size.Width;
@@ -143,13 +153,11 @@ namespace Avalonia.Media.TextFormatting
                                                 }
                                         }
                                     }
-                                }
-                                else
-                                {
-                                    collapsedRuns.Add(shapedSymbol);
+
+                                    return collapsedRuns.ToArray();
                                 }
 
-                                return collapsedRuns;
+                                return new TextRun[] { shapedSymbol };
                             }
 
                             availableWidth -= shapedRun.Size.Width;
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextLineImpl.cs b/src/Avalonia.Base/Media/TextFormatting/TextLineImpl.cs
index ab9686a34a..ae6df3a232 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextLineImpl.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextLineImpl.cs
@@ -1,19 +1,18 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using Avalonia.Utilities;
 
 namespace Avalonia.Media.TextFormatting
 {
-    internal class TextLineImpl : TextLine
+    internal sealed class TextLineImpl : TextLine
     {
-        private IReadOnlyList<TextRun> _textRuns;
+        private TextRun[] _textRuns;
         private readonly double _paragraphWidth;
         private readonly TextParagraphProperties _paragraphProperties;
         private TextLineMetrics _textLineMetrics;
         private readonly FlowDirection _resolvedFlowDirection;
 
-        public TextLineImpl(IReadOnlyList<TextRun> textRuns, int firstTextSourceIndex, int length, double paragraphWidth,
+        public TextLineImpl(TextRun[] textRuns, int firstTextSourceIndex, int length, double paragraphWidth,
             TextParagraphProperties paragraphProperties, FlowDirection resolvedFlowDirection = FlowDirection.LeftToRight,
             TextLineBreak? lineBreak = null, bool hasCollapsed = false)
         {
@@ -147,7 +146,7 @@ namespace Avalonia.Media.TextFormatting
             var collapsedLine = new TextLineImpl(collapsedRuns, FirstTextSourceIndex, Length, _paragraphWidth, _paragraphProperties,
                 _resolvedFlowDirection, TextLineBreak, true);
 
-            if (collapsedRuns.Count > 0)
+            if (collapsedRuns.Length > 0)
             {
                 collapsedLine.FinalizeLine();
             }
@@ -166,7 +165,7 @@ namespace Avalonia.Media.TextFormatting
         /// <inheritdoc/>
         public override CharacterHit GetCharacterHitFromDistance(double distance)
         {
-            if (_textRuns.Count == 0)
+            if (_textRuns.Length == 0)
             {
                 return new CharacterHit();
             }
@@ -182,7 +181,7 @@ namespace Avalonia.Media.TextFormatting
 
             if (distance >= WidthIncludingTrailingWhitespace)
             {
-                var lastRun = _textRuns[_textRuns.Count - 1];
+                var lastRun = _textRuns[_textRuns.Length - 1];
 
                 var size = 0.0;
 
@@ -199,7 +198,7 @@ namespace Avalonia.Media.TextFormatting
             var currentPosition = FirstTextSourceIndex;
             var currentDistance = 0.0;
 
-            for (var i = 0; i < _textRuns.Count; i++)
+            for (var i = 0; i < _textRuns.Length; i++)
             {
                 var currentRun = _textRuns[i];
 
@@ -208,7 +207,7 @@ namespace Avalonia.Media.TextFormatting
                     var rightToLeftIndex = i;
                     currentPosition += currentRun.Length;
 
-                    while (rightToLeftIndex + 1 <= _textRuns.Count - 1)
+                    while (rightToLeftIndex + 1 <= _textRuns.Length - 1)
                     {
                         var nextShaped = _textRuns[++rightToLeftIndex] as ShapedTextRun;
 
@@ -224,7 +223,7 @@ namespace Avalonia.Media.TextFormatting
 
                     for (var j = i; i <= rightToLeftIndex; j++)
                     {
-                        if (j > _textRuns.Count - 1)
+                        if (j > _textRuns.Length - 1)
                         {
                             break;
                         }
@@ -254,7 +253,7 @@ namespace Avalonia.Media.TextFormatting
 
                 if (currentRun is DrawableTextRun drawableTextRun)
                 {
-                    if (i < _textRuns.Count - 1 && currentDistance + drawableTextRun.Size.Width < distance)
+                    if (i < _textRuns.Length - 1 && currentDistance + drawableTextRun.Size.Width < distance)
                     {
                         currentDistance += drawableTextRun.Size.Width;
 
@@ -328,7 +327,7 @@ namespace Avalonia.Media.TextFormatting
 
             if (flowDirection == FlowDirection.LeftToRight)
             {
-                for (var index = 0; index < _textRuns.Count; index++)
+                for (var index = 0; index < _textRuns.Length; index++)
                 {
                     var currentRun = _textRuns[index];
 
@@ -338,7 +337,7 @@ namespace Avalonia.Media.TextFormatting
 
                         var rightToLeftWidth = shapedRun.Size.Width;
 
-                        while (i + 1 <= _textRuns.Count - 1)
+                        while (i + 1 <= _textRuns.Length - 1)
                         {
                             var nextRun = _textRuns[i + 1];
 
@@ -402,7 +401,7 @@ namespace Avalonia.Media.TextFormatting
             {
                 currentDistance += WidthIncludingTrailingWhitespace;
 
-                for (var index = _textRuns.Count - 1; index >= 0; index--)
+                for (var index = _textRuns.Length - 1; index >= 0; index--)
                 {
                     var currentRun = _textRuns[index];
 
@@ -502,7 +501,7 @@ namespace Avalonia.Media.TextFormatting
         /// <inheritdoc/>
         public override CharacterHit GetNextCaretCharacterHit(CharacterHit characterHit)
         {
-            if (_textRuns.Count == 0)
+            if (_textRuns.Length == 0)
             {
                 return new CharacterHit();
             }
@@ -637,7 +636,7 @@ namespace Avalonia.Media.TextFormatting
                         var rightToLeftIndex = index;
                         var rightToLeftWidth = currentShapedRun.Size.Width;
 
-                        while (rightToLeftIndex + 1 <= _textRuns.Count - 1 && _textRuns[rightToLeftIndex + 1] is ShapedTextRun nextShapedRun)
+                        while (rightToLeftIndex + 1 <= _textRuns.Length - 1 && _textRuns[rightToLeftIndex + 1] is ShapedTextRun nextShapedRun)
                         {
                             if (nextShapedRun == null || nextShapedRun.ShapedBuffer.IsLeftToRight)
                             {
@@ -981,7 +980,7 @@ namespace Avalonia.Media.TextFormatting
 
         public override void Dispose()
         {
-            for (int i = 0; i < _textRuns.Count; i++)
+            for (int i = 0; i < _textRuns.Length; i++)
             {
                 if (_textRuns[i] is ShapedTextRun shapedTextRun)
                 {
@@ -1013,7 +1012,7 @@ namespace Avalonia.Media.TextFormatting
 
         private void BidiReorder()
         {
-            if (_textRuns.Count == 0)
+            if (_textRuns.Length == 0)
             {
                 return;
             }
@@ -1025,7 +1024,7 @@ namespace Avalonia.Media.TextFormatting
 
             var current = orderedRun;
 
-            for (var i = 1; i < _textRuns.Count; i++)
+            for (var i = 1; i < _textRuns.Length; i++)
             {
                 run = _textRuns[i];
 
@@ -1044,7 +1043,7 @@ namespace Avalonia.Media.TextFormatting
             sbyte max = 0;
             var min = sbyte.MaxValue;
 
-            for (var i = 0; i < _textRuns.Count; i++)
+            for (var i = 0; i < _textRuns.Length; i++)
             {
                 var currentRun = _textRuns[i];
 
@@ -1095,13 +1094,14 @@ namespace Avalonia.Media.TextFormatting
                 minLevelToReverse--;
             }
 
-            var textRuns = new List<TextRun>(_textRuns.Count);
+            var textRuns = new TextRun[_textRuns.Length];
+            var index = 0;
 
             current = orderedRun;
 
             while (current != null)
             {
-                textRuns.Add(current.Run);
+                textRuns[index++] = current.Run;
 
                 current = current.Next;
             }
@@ -1197,7 +1197,7 @@ namespace Avalonia.Media.TextFormatting
 
             var runIndex = GetRunIndexAtCharacterIndex(codepointIndex, LogicalDirection.Forward, out var currentPosition);
 
-            while (runIndex < _textRuns.Count)
+            while (runIndex < _textRuns.Length)
             {
                 var currentRun = _textRuns[runIndex];
 
@@ -1346,7 +1346,7 @@ namespace Avalonia.Media.TextFormatting
             textPosition = FirstTextSourceIndex;
             TextRun? previousRun = null;
 
-            while (runIndex < _textRuns.Count)
+            while (runIndex < _textRuns.Length)
             {
                 var currentRun = _textRuns[runIndex];
 
@@ -1395,7 +1395,7 @@ namespace Avalonia.Media.TextFormatting
                                 }
                             }
 
-                            if (runIndex + 1 >= _textRuns.Count)
+                            if (runIndex + 1 >= _textRuns.Length)
                             {
                                 return runIndex;
                             }
@@ -1411,7 +1411,7 @@ namespace Avalonia.Media.TextFormatting
                                 return runIndex;
                             }
 
-                            if (runIndex + 1 >= _textRuns.Count)
+                            if (runIndex + 1 >= _textRuns.Length)
                             {
                                 return runIndex;
                             }
@@ -1448,14 +1448,14 @@ namespace Avalonia.Media.TextFormatting
 
             var lineHeight = _paragraphProperties.LineHeight;
 
-            var lastRunIndex = _textRuns.Count - 1;
+            var lastRunIndex = _textRuns.Length - 1;
 
             if (lastRunIndex > 0 && _textRuns[lastRunIndex] is TextEndOfLine)
             {
                 lastRunIndex--;
             }
 
-            for (var index = 0; index < _textRuns.Count; index++)
+            for (var index = 0; index < _textRuns.Length; index++)
             {
                 switch (_textRuns[index])
                 {
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextTrailingCharacterEllipsis.cs b/src/Avalonia.Base/Media/TextFormatting/TextTrailingCharacterEllipsis.cs
index deecbbe476..ccae99cc75 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextTrailingCharacterEllipsis.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextTrailingCharacterEllipsis.cs
@@ -1,6 +1,4 @@
-using System.Collections.Generic;
-
-namespace Avalonia.Media.TextFormatting
+namespace Avalonia.Media.TextFormatting
 {
     /// <summary>
     /// A collapsing properties to collapse whole line toward the end
@@ -26,7 +24,8 @@ namespace Avalonia.Media.TextFormatting
         /// <inheritdoc/>
         public override TextRun Symbol { get; }
 
-        public override List<TextRun>? Collapse(TextLine textLine)
+        /// <inheritdoc />
+        public override TextRun[]? Collapse(TextLine textLine)
         {
             return TextEllipsisHelper.Collapse(textLine, this, false);
         }
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextTrailingWordEllipsis.cs b/src/Avalonia.Base/Media/TextFormatting/TextTrailingWordEllipsis.cs
index c291e1dfb9..c622c76a60 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextTrailingWordEllipsis.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextTrailingWordEllipsis.cs
@@ -1,7 +1,4 @@
-using System.Collections.Generic;
-using Avalonia.Utilities;
-
-namespace Avalonia.Media.TextFormatting
+namespace Avalonia.Media.TextFormatting
 {
     /// <summary>
     /// a collapsing properties to collapse whole line toward the end
@@ -31,7 +28,8 @@ namespace Avalonia.Media.TextFormatting
         /// <inheritdoc/>
         public override TextRun Symbol { get; }
 
-        public override List<TextRun>? Collapse(TextLine textLine)
+        /// <inheritdoc />
+        public override TextRun[]? Collapse(TextLine textLine)
         {
             return TextEllipsisHelper.Collapse(textLine, this, true);
         }