diff --git a/editor.lib/src/org/netbeans/editor/DrawEngineLineView.java b/editor.lib/src/org/netbeans/editor/DrawEngineLineView.java
--- a/editor.lib/src/org/netbeans/editor/DrawEngineLineView.java
+++ b/editor.lib/src/org/netbeans/editor/DrawEngineLineView.java
@@ -52,6 +52,7 @@
 import javax.swing.text.Element;
 import javax.swing.text.JTextComponent;
 import javax.swing.text.Position;
+import javax.swing.text.Position.Bias;
 import javax.swing.text.View;
 import javax.swing.text.ViewFactory;
 import org.netbeans.editor.view.spi.EstimatedSpanView;
@@ -894,5 +895,40 @@
         }
         
     } // End of FragmentView class
-    
+
+	// #164820
+	@Override
+	public int getNextVisualPositionFrom(int pos, Bias b, Shape a, int direction, Bias[] biasRet) throws BadLocationException {
+		
+		switch (direction) {
+		case WEST:
+			{
+				pos = super.getNextVisualPositionFrom(pos, b, a, direction, biasRet);
+				char[] chars = getDocument().getText(pos, 1).toCharArray();
+				if (chars.length > 0 && Character.isLowSurrogate(chars[0])) {
+					// Supplementary character
+					return super.getNextVisualPositionFrom(pos, b, a, direction, biasRet);
+				}
+			}
+			break;
+
+		case EAST:
+			{
+				pos = super.getNextVisualPositionFrom(pos, b, a, direction, biasRet);
+				char[] chars = getDocument().getText(pos, 1).toCharArray();
+				if (chars.length > 0 && Character.isLowSurrogate(chars[0])) {
+					// Supplementary character
+					return super.getNextVisualPositionFrom(pos, b, a, direction, biasRet);
+				}
+			}
+			break;
+
+		default:
+			pos = super.getNextVisualPositionFrom(pos, b, a, direction, biasRet);
+			break;
+		}
+
+		return pos;
+	}
+	
 }
diff --git a/editor.lib/src/org/netbeans/editor/Mark.java b/editor.lib/src/org/netbeans/editor/Mark.java
--- a/editor.lib/src/org/netbeans/editor/Mark.java
+++ b/editor.lib/src/org/netbeans/editor/Mark.java
@@ -47,6 +47,7 @@
 import javax.swing.text.BadLocationException;
 import javax.swing.text.Element;
 import javax.swing.text.Position;
+import javax.swing.text.Position.Bias;
 
 /**
 * Marks hold the relative position in the document.
@@ -109,9 +110,25 @@
                 + ", class=" + this.getClass()); // NOI18N
             }
 
-            if (offset < 0 || offset > ldoc.getLength() + 1) { // doc.getEndPosition() is valid
-                throw new BadLocationException("Invalid offset", offset); // NOI18N
-            }
+			if (offset < 0 || offset > ldoc.getLength() + 1) { // doc.getEndPosition() is valid
+				throw new BadLocationException("Invalid offset", offset); // NOI18N
+			}
+
+			// Deal with supplementary characters #164820
+			char[] chars = doc.getText(offset, 1).toCharArray();
+			if (chars.length > 0 && Character.isLowSurrogate(chars[0])) {
+				if (bias == Bias.Forward && offset < ldoc.getLength()) {
+					offset++;
+
+				} else if (bias == Bias.Backward && offset > 0) {
+					offset--;
+				}
+				
+				// If there is still a low surrogate after recalculating,
+				// treat it as an invalid document, just ignore and pass through.
+				// Since there should be a surrogate pair in Java and Unicode to
+				// represent a supplementary character.
+			}
 
             multiMark = doc.marksStorage.createBiasMark(offset, bias);
             doc.marksStorage.insert(multiMark);
diff --git a/editor.lib/src/org/netbeans/editor/Utilities.java b/editor.lib/src/org/netbeans/editor/Utilities.java
--- a/editor.lib/src/org/netbeans/editor/Utilities.java
+++ b/editor.lib/src/org/netbeans/editor/Utilities.java
@@ -355,18 +355,38 @@
         int best = findBestSpan(c, start, end, x);
         
         if (best<c.getDocument().getLength()){
-            // #56056
-            int tmp = best + 1;
-            int nextVisualPosition = c.getUI().getNextVisualPositionFrom(c,
-                    tmp, javax.swing.text.Position.Bias.Backward, javax.swing.SwingConstants.WEST, null);
+			// #56056
+			int tmp = best + 1;
+			int nextVisualPosition = c.getUI().getNextVisualPositionFrom(c,
+					tmp, javax.swing.text.Position.Bias.Backward, javax.swing.SwingConstants.WEST, null);
             if (nextVisualPosition<best && nextVisualPosition >= 0){
-                return nextVisualPosition;
-            }
+				// #164820
+				// We are in the collapsed fold, now try to find which position
+				// is the best, whether foldEnd or foldStart
+				tempRect = c.modelToView(nextVisualPosition);
+				if (tempRect == null) {
+					return nextVisualPosition;
+				}
+				int leftX = tempRect.x;
+				int nextVisualPositionRight = c.getUI().getNextVisualPositionFrom(c,
+						nextVisualPosition, javax.swing.text.Position.Bias.Forward, javax.swing.SwingConstants.EAST, null);
+				tempRect = c.modelToView(nextVisualPositionRight);
+				if (tempRect == null) {
+					return nextVisualPosition;
+				}
+				int rightX = tempRect.x;
+
+				if (Math.abs(leftX - x) < Math.abs(rightX - x)) {
+					return nextVisualPosition;
+				} else {
+					return nextVisualPositionRight;
+				}
+			}
         }
-        
+
         return best;
-    }    
-    
+    }
+
     /** Get the position that is one line above and visually at some
     * x-coordinate value.
     * @param c text component to operate on