Fix bug.

Runtime/painting/text_painter.cs

-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using Unity.UIWidgets.foundation;
 using Unity.UIWidgets.service;
 using Unity.UIWidgets.ui;
                 var builder = new ParagraphBuilder(this._createParagraphStyle());
                 this._text.build(builder, this.textScaleFactor);
                 this._paragraph = builder.build();
+            }
+            else {
+                Debug.Log($"Use Old Paragraph [{DateTime.Now.Millisecond}]");
             }
 
             this._lastMinWidth = minWidth;

Runtime/ui/txt/paragraph.cs

         }
 
         public void layout(ParagraphConstraints constraints) {
-            if ((!this._needsLayout && this._width == constraints.width) ||
-                this._text == null || this._text.isEmpty()) {
+            if (!this._needsLayout && this._width == constraints.width) {
                 return;
             }
 
                             int textCount = textEnd - textStart;
                             // Keep track of the pointer to _glyphPositions in the start of this run
                             int glyphPositionStyleRunStart = pGlyphPositions;
+                            Font font = FontManager.instance.getOrCreate(
+                                style.fontFamily,
+                                style.fontWeight,
+                                style.fontStyle).font;
 
                             // Ellipsize the text if ellipsis string is set, and this is the last lineStyleRun of
                             // the current line, and this is the last line or max line is not set
+                                font.RequestCharactersInTextureSafe(ellipsis, style.UnityFontSize, style.UnityFontStyle);
                                 float ellipsisWidth = Layout.measureText(ellipsis, style);
 
                                 // Find the minimum number of characters to truncate, so that the truncated text
                             }
 
                             // Create paint record
-                            var font = FontManager.instance.getOrCreate(style.fontFamily,
-                                style.fontWeight, style.fontStyle).font;
                             var metrics = FontMetrics.fromFont(font, style.UnityFontSize);
                             PaintRecord paintRecord = new PaintRecord(style, runXOffset, 0, builder.make(),
                                 metrics, advance);