diff -r 9df25b7cacc3 src/EditView.cxx
--- a/src/EditView.cxx	Mon Mar 02 19:27:58 2026 +1100
+++ b/src/EditView.cxx	Wed Mar 04 15:46:33 2026 +1100
@@ -828,6 +828,13 @@
 
 namespace {
 
+constexpr PRectangle Larger(const PRectangle &rc, [[maybe_unused]] XYPOSITION delta) noexcept {
+	// Extend bottom-right to make larger by delta pixels
+	return PRectangle(rc.left, rc.top, rc.right + delta, rc.bottom + delta);
+	//return rc;
+}
+
+
 constexpr ColourRGBA colourBug(0xff, 0, 0xfe, 0xf0);
 
 // Selection background colours are always defined, the value_or is to show if bug
@@ -921,7 +928,7 @@
 }
 
 void FillLineRemainder(Surface *surface, const EditModel &model, const ViewStyle &vsDraw, const LineLayout *ll,
-	Sci::Line line, PRectangle rcLine, XYPOSITION left, int subLine) {
+	Sci::Line line, PRectangle rcLine, XYPOSITION left, int subLine, XYPOSITION seamOverDraw) {
 	if (rcLine.Empty()) {
 		return;
 	}
@@ -931,7 +938,7 @@
 	}
 	const bool drawEOLSelection = eolInSelection && vsDraw.selection.eolFilled && (line < model.pdoc->LinesTotal() - 1);
 
-	const PRectangle rcArea = Clamp(rcLine, Edge::left, left);	// Limit to right side of line from 'left'
+	const PRectangle rcArea = Larger(Clamp(rcLine, Edge::left, left), seamOverDraw);	// Limit to right side of line from 'left'
 
 	const ColourRGBA selectionBack = drawEOLSelection ? SelectionBackground(model, vsDraw, eolInSelection) : ColourRGBA{};
 	ColourRGBA base = vsDraw.styles[StyleDefault].back;
@@ -1113,16 +1120,16 @@
 	} else if (const Style &styleLast = vsDraw.styles[ll->LastStyle()]; styleLast.eolFilled) {
 		base = styleLast.back;
 	}
-	surface->FillRectangleAligned(rcEOLIsSelected, Fill(base.Opaque()));
+	surface->FillRectangleAligned(Larger(rcEOLIsSelected, seamOverDraw), Fill(base.Opaque()));
 	if (drawEOLSelection && (vsDraw.selection.layer != Layer::Base)) {
-		surface->FillRectangleAligned(rcEOLIsSelected, selectionBack);
+		surface->FillRectangleAligned(Larger(rcEOLIsSelected, seamOverDraw), selectionBack);
 	}
 
 	const bool drawEOLAnnotationStyledText = (vsDraw.eolAnnotationVisible != EOLAnnotationVisible::Hidden) && model.pdoc->EOLAnnotationStyledText(line).text;
 	const bool fillRemainder = (!lastSubLine || (!model.GetFoldDisplayText(line) && !drawEOLAnnotationStyledText));
 	if (fillRemainder) {
 		// Fill the remainder of the line
-		FillLineRemainder(surface, model, vsDraw, ll, line, rcLine, rcEOLIsSelected.right, subLine);
+		FillLineRemainder(surface, model, vsDraw, ll, line, rcLine, rcEOLIsSelected.right, subLine, seamOverDraw);
 	}
 
 	bool drawWrapMarkEnd = false;
@@ -1198,7 +1205,7 @@
 		surface->FillRectangleAligned(rcSegment, Fill(textBack));
 
 		// Fill Remainder of the line
-		FillLineRemainder(surface, model, vsDraw, ll, line, rcLine, rcSegment.right, subLine);
+		FillLineRemainder(surface, model, vsDraw, ll, line, rcLine, rcSegment.right, subLine, seamOverDraw);
 	}
 
 	if (FlagSet(phase, DrawPhase::text)) {
@@ -1286,8 +1293,8 @@
 		// it may be double drawing. This is to allow stadiums with
 		// curved or angled ends to have the area outside in the correct
 		// background colour.
-		surface->FillRectangleAligned(rcSegment, Fill(textBack));
-		FillLineRemainder(surface, model, vsDraw, ll, line, rcLine, rcSegment.right, subLine);
+		surface->FillRectangleAligned(Larger(rcSegment, seamOverDraw), Fill(textBack));
+		FillLineRemainder(surface, model, vsDraw, ll, line, rcLine, rcSegment.right, subLine, seamOverDraw);
 	}
 
 	const PRectangle rcText = TextPart(rcSegment, padding);
@@ -1640,7 +1647,7 @@
 
 void DrawBackground(Surface *surface, const EditModel &model, const ViewStyle &vsDraw, const LineLayout *ll,
 	int xStart, PRectangle rcLine, int subLine, Range lineRange, Sci::Position posLineStart,
-	ColourOptional background) {
+	ColourOptional background, XYPOSITION seamOverDraw) {
 
 	const bool selBackDrawn = vsDraw.SelectionBackgroundDrawn();
 	bool inIndentation = subLine == 0;	// Do not handle indentation except on first subline.
@@ -1683,17 +1690,17 @@
 					// Blob display
 					inIndentation = false;
 				}
-				surface->FillRectangleAligned(rcSegment, Fill(textBack));
-			} else {
+			}
+			surface->FillRectangleAligned(Larger(rcSegment, seamOverDraw), Fill(textBack));
+			if (!ts.representation) {
 				// Normal text display
-				surface->FillRectangleAligned(rcSegment, Fill(textBack));
 				if (vsDraw.viewWhitespace != WhiteSpace::Invisible) {
 					for (int cpos = 0; cpos <= i - ts.start; cpos++) {
 						if (ll->chars[cpos + ts.start] == ' ') {
 							if (drawWhitespaceBackground && vsDraw.WhiteSpaceVisible(inIndentation)) {
 								const PRectangle rcSpace = Intersection(rcLine,
 									ll->SpanByte(cpos + ts.start).Offset(horizontalOffset));
-								surface->FillRectangleAligned(rcSpace,
+								surface->FillRectangleAligned(Larger(rcSpace, seamOverDraw),
 									vsDraw.ElementColourForced(Element::WhiteSpaceBack).Opaque());
 							}
 						} else {
@@ -2380,6 +2387,8 @@
 		surface->SetClip(rcLine);
 	}
 
+	seamOverDraw = (!bufferedDraw && LinesOverlap()) ? 1.0 : 0.0;
+
 	// See if something overrides the line background colour.
 	const ColourOptional background = vsDraw.Background(model.GetMark(line), model.caret.active, ll->containsCaret);
 
@@ -2400,7 +2409,7 @@
 		if (FlagSet(phase, DrawPhase::back)) {
 			DrawBackground(surface, model, vsDraw, ll,
 				xStart, rcLine, subLine, lineRange, posLineStart,
-				background);
+				background, seamOverDraw);
 			DrawFoldDisplayText(surface, model, vsDraw, ll, line, xStart, rcLine, subLine, subLineStart, DrawPhase::back);
 			DrawEOLAnnotationText(surface, model, vsDraw, ll, line, xStart, rcLine, subLine, subLineStart, DrawPhase::back);
 			// Remove drawBack to not draw again in DrawFoldDisplayText
@@ -2514,6 +2523,7 @@
 		double durCopy = 0.0;
 		ElapsedPeriod epWhole;
 #endif
+		surface->FillRectangleAligned(rcTextArea, Fill(ColourRGBA(0,0,0)));
 		const bool bracesIgnoreStyle = ((vsDraw.braceHighlightIndicatorSet && (model.bracesMatchStyle == StyleBraceLight)) ||
 			(vsDraw.braceBadLightIndicatorSet && (model.bracesMatchStyle == StyleBraceBad)));
 
diff -r 9df25b7cacc3 src/EditView.h
--- a/src/EditView.h	Mon Mar 02 19:27:58 2026 +1100
+++ b/src/EditView.h	Wed Mar 04 15:46:33 2026 +1100
@@ -67,6 +67,8 @@
 	* overlap from one line to the next. */
 	Scintilla::PhasesDraw phasesDraw;
 
+	XYPOSITION seamOverDraw = 0;
+
 	int lineWidthMaxSeen;
 
 	bool additionalCaretsBlink;