diff --git a/src/render/katerenderer.h b/src/render/katerenderer.h
--- a/src/render/katerenderer.h
+++ b/src/render/katerenderer.h
@@ -422,6 +422,7 @@
     int m_tabWidth;
     int m_indentWidth;
     int m_fontHeight;
+    mutable int m_textHeight = -1;
 
     // some internal flags
     KateRenderer::caretStyles m_caretStyle;
diff --git a/src/render/katerenderer.cpp b/src/render/katerenderer.cpp
--- a/src/render/katerenderer.cpp
+++ b/src/render/katerenderer.cpp
@@ -536,6 +536,25 @@
     }
 }
 
+static QVector<QTextLayout::FormatRange> decorationsForLineGap(const QVector<QTextLayout::FormatRange> &formats, const QVector<QTextLayout::FormatRange> &additionalFormats) {
+    // We want to make sure that we draw no text for gap, but keep all the
+    // existing background. Based on the logic in QTextLayout::draw, color
+    // without foreground will not draw text.
+    QVector<QTextLayout::FormatRange> gapFormats = formats + additionalFormats;
+    for (auto &format : gapFormats) {
+        format.format.clearForeground();
+    }
+    // Add a dummy selection at the end of formats. It will draw "transparent"
+    // text and background. so no text and background will should be drawn after
+    // hanlding it.
+    gapFormats.append(QTextLayout::FormatRange());
+    gapFormats.back().start = 0;
+    gapFormats.back().length = INT_MAX;
+    gapFormats.back().format.setForeground(Qt::transparent);
+    gapFormats.back().format.setBackground(Qt::transparent);
+    return gapFormats;
+}
+
 void KateRenderer::paintTextLine(QPainter &paint, KateLineLayoutPtr range, int xStart, int xEnd, const KTextEditor::Cursor *cursor, PaintTextLineFlags flags)
 {
     Q_ASSERT(range->isValid());
@@ -589,18 +608,56 @@
 
         QVector<QTextLayout::FormatRange> additionalFormats;
         if (range->length() > 0) {
+            if (drawSelection) {
+                additionalFormats = decorationsForLine(range->textLine(), range->line(), true);
+            }
+
+            // Check if there's any format need to be fill into the gap.
+            auto formats = range->layout()->formats();
+            if (!formats.isEmpty() || !additionalFormats.isEmpty()) {
+                QVector<QTextLayout::FormatRange> gapFormats;
+                for (int i = 0; i < range->layout()->lineCount(); i++) {
+                    auto line = range->layout()->lineAt(i);
+                    // Right now, y should always be multiply of lineHeight.
+                    auto yOffset = qRound(line.y()) % lineHeight();
+                    if (yOffset == 0) {
+                        continue;
+                    }
+                    auto rect = line.rect();
+                    if (rect.height() <= 0) {
+                        continue;
+                    }
+                    auto textHeight = rect.height();
+                    // Only initialize gapFormats once, it will never be empty.
+                    if (gapFormats.isEmpty()) {
+                        gapFormats = decorationsForLineGap(formats, additionalFormats);
+                    }
+                    // The line looks like
+                    // --- y: lineHeight * (i-1)
+                    // gap
+                    // --- y: line.y() = lineHeight * (i-1) + yOffset
+                    // text
+                    // --- y: lineHeight * i
+                    // We want to repeatedly draw "transparent" text in the gap region.
+                    // First we set the clip region to only cover the gap.
+                    rect.moveTop(line.y() - yOffset);
+                    rect.setHeight(yOffset);
+                    auto yStart = -yOffset;
+                    // We use a loop here to fill the yOffset gap with multiple textHeight.
+                    // Under most case, this should be only 0 or 1 extra transparent text
+                    // need to be drawn.
+                    while (yStart < 0) {
+                        range->layout()->draw(&paint, QPoint(-xStart, yStart), gapFormats, rect);
+                        yStart += textHeight;
+                    }
+                }
+            }
             // We may have changed the pen, be absolutely sure it gets set back to
             // normal foreground color before drawing text for text that does not
             // set the pen color
             paint.setPen(attribute(KTextEditor::dsNormal)->foreground().color());
             // Draw the text :)
-            if (drawSelection) {
-                additionalFormats = decorationsForLine(range->textLine(), range->line(), true);
-                range->layout()->draw(&paint, QPoint(-xStart, 0), additionalFormats);
-
-            } else {
-                range->layout()->draw(&paint, QPoint(-xStart, 0));
-            }
+            range->layout()->draw(&paint, QPoint(-xStart, 0), additionalFormats);
         }
 
         QBrush backgroundBrush;
@@ -893,7 +950,7 @@
 
 uint KateRenderer::fontHeight() const
 {
-    return m_fontHeight;
+    return qMax(m_textHeight, m_fontHeight);
 }
 
 uint KateRenderer::documentHeight() const
@@ -964,6 +1021,8 @@
      */
     m_font = config()->baseFont();
     m_fontMetrics = QFontMetricsF(m_font);
+    // Clear the text height based on font.
+    m_textHeight = -1;
 
     /**
      * ensure minimal height of one pixel to not fall in the div by 0 trap somewhere
@@ -1073,6 +1132,7 @@
 
     int height = 0;
     int shiftX = 0;
+    int pendingTextHeight = -1;
 
     bool needShiftX = (maxwidth != -1) && m_view && (m_view->config()->dynWordWrapAlignIndent() > 0);
 
@@ -1084,12 +1144,20 @@
 
         if (maxwidth > 0) {
             line.setLineWidth(maxwidth);
+        } else {
+            line.setLineWidth(INT_MAX);
         }
 
         // we include the leading, this must match the ::updateFontHeight code!
         line.setLeadingIncluded(true);
-
-        line.setPosition(QPoint(line.lineNumber() ? shiftX : firstLineOffset, height));
+        qreal lineOffset = 0;
+        if (line.rect().isValid()) {
+            if (line.height() < lineHeight()) {
+                lineOffset = lineHeight() - line.height();
+            }
+            pendingTextHeight = qMax(qCeil(line.height()), pendingTextHeight);
+        }
+        line.setPosition(QPointF(line.lineNumber() ? shiftX : firstLineOffset, height + lineOffset));
 
         if (needShiftX && line.width() > 0) {
             needShiftX = false;
@@ -1117,6 +1185,12 @@
     l->endLayout();
 
     lineLayout->setLayout(l);
+
+    if (cacheLayout && pendingTextHeight > lineHeight()) {
+        m_textHeight = pendingTextHeight;
+        // trigger view update, if any!
+        QMetaObject::invokeMethod(m_view, "updateRendererConfig", Qt::QueuedConnection);
+    }
 }
 
 // 1) QString::isRightToLeft() sux
diff --git a/src/view/kateview.h b/src/view/kateview.h
--- a/src/view/kateview.h
+++ b/src/view/kateview.h
@@ -799,7 +799,7 @@
 
     void updateDocumentConfig();
 
-    void updateRendererConfig();
+    Q_INVOKABLE void updateRendererConfig();
 
 private Q_SLOTS:
     void updateFoldingConfig();