diff --git a/packages/flutter_markdown/CHANGELOG.md b/packages/flutter_markdown/CHANGELOG.md
index 152186a797..cb162efb0f 100644
--- a/packages/flutter_markdown/CHANGELOG.md
+++ b/packages/flutter_markdown/CHANGELOG.md
@@ -1,3 +1,8 @@
+## 0.4.3
+
+ * Fix merging of `MarkdownStyleSheets`
+ * Fix if not provided in `MarkdownStyleSheet` textScaleFactor uses default value of 1.0 instead using the textScaleFactor of the nearest MediaQuery 
+
 ## 0.4.2
 
  * Fix parsing of image caption & alt attributes
diff --git a/packages/flutter_markdown/lib/src/_functions_io.dart b/packages/flutter_markdown/lib/src/_functions_io.dart
index 4bd198767c..fccdcb9fa8 100644
--- a/packages/flutter_markdown/lib/src/_functions_io.dart
+++ b/packages/flutter_markdown/lib/src/_functions_io.dart
@@ -43,17 +43,25 @@ final MarkdownStyleSheet Function(BuildContext, MarkdownStyleSheetBaseTheme)
   BuildContext context,
   MarkdownStyleSheetBaseTheme baseTheme,
 ) {
+  MarkdownStyleSheet result;
   switch (baseTheme) {
     case MarkdownStyleSheetBaseTheme.platform:
-      return (Platform.isIOS || Platform.isMacOS)
+      result = (Platform.isIOS || Platform.isMacOS)
           ? MarkdownStyleSheet.fromCupertinoTheme(CupertinoTheme.of(context))
           : MarkdownStyleSheet.fromTheme(Theme.of(context));
+      break;
     case MarkdownStyleSheetBaseTheme.cupertino:
-      return MarkdownStyleSheet.fromCupertinoTheme(CupertinoTheme.of(context));
+      result =
+          MarkdownStyleSheet.fromCupertinoTheme(CupertinoTheme.of(context));
+      break;
     case MarkdownStyleSheetBaseTheme.material:
     default:
-      return MarkdownStyleSheet.fromTheme(Theme.of(context));
+      result = MarkdownStyleSheet.fromTheme(Theme.of(context));
   }
+
+  return result.copyWith(
+    textScaleFactor: MediaQuery.textScaleFactorOf(context),
+  );
 };
 
 Widget _handleDataSchemeUri(Uri uri, final double width, final double height) {
diff --git a/packages/flutter_markdown/lib/src/_functions_web.dart b/packages/flutter_markdown/lib/src/_functions_web.dart
index 2fdf2a004f..d6800982c8 100644
--- a/packages/flutter_markdown/lib/src/_functions_web.dart
+++ b/packages/flutter_markdown/lib/src/_functions_web.dart
@@ -43,18 +43,26 @@ final MarkdownStyleSheet Function(BuildContext, MarkdownStyleSheetBaseTheme)
   BuildContext context,
   MarkdownStyleSheetBaseTheme baseTheme,
 ) {
+  MarkdownStyleSheet result;
   switch (baseTheme) {
     case MarkdownStyleSheetBaseTheme.platform:
       final String userAgent = window.navigator.userAgent;
-      return userAgent.contains('Mac OS X')
+      result = userAgent.contains('Mac OS X')
           ? MarkdownStyleSheet.fromCupertinoTheme(CupertinoTheme.of(context))
           : MarkdownStyleSheet.fromTheme(Theme.of(context));
+      break;
     case MarkdownStyleSheetBaseTheme.cupertino:
-      return MarkdownStyleSheet.fromCupertinoTheme(CupertinoTheme.of(context));
+      result =
+          MarkdownStyleSheet.fromCupertinoTheme(CupertinoTheme.of(context));
+      break;
     case MarkdownStyleSheetBaseTheme.material:
     default:
-      return MarkdownStyleSheet.fromTheme(Theme.of(context));
+      result = MarkdownStyleSheet.fromTheme(Theme.of(context));
   }
+
+  return result.copyWith(
+    textScaleFactor: MediaQuery.textScaleFactorOf(context),
+  );
 };
 
 Widget _handleDataSchemeUri(Uri uri, final double width, final double height) {
diff --git a/packages/flutter_markdown/lib/src/builder.dart b/packages/flutter_markdown/lib/src/builder.dart
index c42fdb20e7..05e5437594 100644
--- a/packages/flutter_markdown/lib/src/builder.dart
+++ b/packages/flutter_markdown/lib/src/builder.dart
@@ -577,7 +577,7 @@ class MarkdownBuilder implements md.NodeVisitor {
     if (selectable) {
       return SelectableText.rich(
         text,
-        //textScaleFactor: styleSheet.textScaleFactor,
+        textScaleFactor: styleSheet.textScaleFactor,
         textAlign: textAlign ?? TextAlign.start,
       );
     } else {
diff --git a/packages/flutter_markdown/lib/src/style_sheet.dart b/packages/flutter_markdown/lib/src/style_sheet.dart
index 71c62945ec..b77045c762 100644
--- a/packages/flutter_markdown/lib/src/style_sheet.dart
+++ b/packages/flutter_markdown/lib/src/style_sheet.dart
@@ -50,7 +50,7 @@ class MarkdownStyleSheet {
     this.orderedListAlign = WrapAlignment.start,
     this.blockquoteAlign = WrapAlignment.start,
     this.codeblockAlign = WrapAlignment.start,
-    this.textScaleFactor = 1.0,
+    this.textScaleFactor,
   }) : _styles = <String, TextStyle>{
           'a': a,
           'p': p,
@@ -130,6 +130,7 @@ class MarkdownStyleSheet {
           ),
         ),
       ),
+      // textScaleFactor: 
     );
   }
 
@@ -394,26 +395,26 @@ class MarkdownStyleSheet {
   MarkdownStyleSheet merge(MarkdownStyleSheet other) {
     if (other == null) return this;
     return copyWith(
-      a: other.a,
-      p: other.p,
-      code: other.code,
-      h1: other.h1,
-      h2: other.h2,
-      h3: other.h3,
-      h4: other.h4,
-      h5: other.h5,
-      h6: other.h6,
-      em: other.em,
-      strong: other.strong,
-      del: other.del,
-      blockquote: other.blockquote,
-      img: other.img,
-      checkbox: other.checkbox,
+      a: a.merge(other.a),
+      p: p.merge(other.p),
+      code: code.merge(other.code),
+      h1: h1.merge(other.h1),
+      h2: h2.merge(other.h2),
+      h3: h3.merge(other.h3),
+      h4: h4.merge(other.h4),
+      h5: h5.merge(other.h5),
+      h6: h6.merge(other.h6),
+      em: em.merge(other.em),
+      strong: strong.merge(other.strong),
+      del: del.merge(other.del),
+      blockquote: blockquote.merge(other.blockquote),
+      img: img.merge(other.img),
+      checkbox: checkbox.merge(other.checkbox),
       blockSpacing: other.blockSpacing,
       listIndent: other.listIndent,
-      listBullet: other.listBullet,
-      tableHead: other.tableHead,
-      tableBody: other.tableBody,
+      listBullet: listBullet.merge(other.listBullet),
+      tableHead: tableHead.merge(other.tableHead),
+      tableBody: tableBody.merge(other.tableBody),
       tableHeadAlign: other.tableHeadAlign,
       tableBorder: other.tableBorder,
       tableColumnWidth: other.tableColumnWidth,
diff --git a/packages/flutter_markdown/test/flutter_markdown_test.dart b/packages/flutter_markdown/test/flutter_markdown_test.dart
index 67527dc314..3cc6cd28d9 100644
--- a/packages/flutter_markdown/test/flutter_markdown_test.dart
+++ b/packages/flutter_markdown/test/flutter_markdown_test.dart
@@ -779,6 +779,39 @@ void main() {
       final RichText richText = tester.widget(find.byType(RichText));
       expect(richText.textScaleFactor, 2.0);
     });
+
+    testWidgets(' - should use MediaQuery textScaleFactor in RichText',
+        (WidgetTester tester) async {
+      await tester.pumpWidget(_boilerplate(
+        MediaQuery(
+          data: MediaQueryData(textScaleFactor: 2.0),
+          child: MarkdownBody(
+            data: 'Hello',
+          ),
+        ),
+      ));
+
+      final RichText richText = tester.widget(find.byType(RichText));
+      expect(richText.textScaleFactor, 2.0);
+    });
+
+    testWidgets(
+        ' - should use MediaQuery textScaleFactor in SelectableText.rich',
+        (WidgetTester tester) async {
+      await tester.pumpWidget(_boilerplate(
+        MediaQuery(
+          data: MediaQueryData(textScaleFactor: 2.0),
+          child: MarkdownBody(
+            data: 'Hello',
+            selectable: true,
+          ),
+        ),
+      ));
+
+      final SelectableText selectableText =
+          tester.widget(find.byType(SelectableText));
+      expect(selectableText.textScaleFactor, 2.0);
+    });
   });
 
   group('Custom builders', () {
@@ -995,11 +1028,15 @@ void main() {
     testWidgets('merge', (WidgetTester tester) async {
       final ThemeData theme = ThemeData.light().copyWith(textTheme: textTheme);
       final MarkdownStyleSheet style1 = MarkdownStyleSheet.fromTheme(theme);
-      final MarkdownStyleSheet style2 =
-          MarkdownStyleSheet(p: TextStyle(color: Colors.red));
+      final MarkdownStyleSheet style2 = MarkdownStyleSheet(
+        p: TextStyle(color: Colors.red),
+        blockquote: TextStyle(fontSize: 16),
+      );
 
       final MarkdownStyleSheet merged = style1.merge(style2);
       expect(merged.p.color, Colors.red);
+      expect(merged.blockquote.fontSize, 16);
+      expect(merged.blockquote.color, theme.textTheme.bodyText2.color);
     });
 
     testWidgets('create based on which theme', (WidgetTester tester) async {