diff --git a/src/Views/Blame.axaml.cs b/src/Views/Blame.axaml.cs
index 5492cba7..9de8a9cf 100644
--- a/src/Views/Blame.axaml.cs
+++ b/src/Views/Blame.axaml.cs
@@ -172,10 +172,7 @@ namespace SourceGit.Views {
             }
 
             _textMate = this.InstallTextMate(_registryOptions);
-
-            if (BlameData != null) {
-                _textMate.SetGrammar(_registryOptions.GetScopeByExtension(Path.GetExtension(BlameData.File)));
-            }
+            UpdateGrammar();
         }
 
         protected override void OnUnloaded(RoutedEventArgs e) {
@@ -195,7 +192,7 @@ namespace SourceGit.Views {
             if (change.Property == BlameDataProperty) {
                 if (BlameData != null) {
                     Text = BlameData.Content;
-                    if (_textMate != null) _textMate.SetGrammar(_registryOptions.GetScopeByExtension(Path.GetExtension(BlameData.File)));
+                    UpdateGrammar();
                 } else {
                     Text = string.Empty;
                 }
@@ -232,6 +229,17 @@ namespace SourceGit.Views {
             e.Handled = true;
         }
 
+        private void UpdateGrammar() {
+            if (_textMate == null || BlameData == null) return;
+
+            var ext = Path.GetExtension(BlameData.File);
+            if (ext == ".h") {
+                _textMate.SetGrammar(_registryOptions.GetScopeByLanguageId("cpp"));
+            } else {
+                _textMate.SetGrammar(_registryOptions.GetScopeByExtension(ext));
+            }
+        }
+
         private RegistryOptions _registryOptions = null;
         private TextMate.Installation _textMate = null;
     }
diff --git a/src/Views/RevisionFiles.axaml.cs b/src/Views/RevisionFiles.axaml.cs
index 2e1778f3..013607a1 100644
--- a/src/Views/RevisionFiles.axaml.cs
+++ b/src/Views/RevisionFiles.axaml.cs
@@ -39,10 +39,7 @@ namespace SourceGit.Views {
             }
 
             _textMate = this.InstallTextMate(_registryOptions);
-
-            if (DataContext != null && DataContext is Models.RevisionTextFile source) {
-                _textMate.SetGrammar(_registryOptions.GetScopeByExtension(Path.GetExtension(source.FileName)));
-            }
+            UpdateGrammar();
         }
 
         protected override void OnUnloaded(RoutedEventArgs e) {
@@ -60,7 +57,7 @@ namespace SourceGit.Views {
 
             var source = DataContext as Models.RevisionTextFile;
             if (source != null) {
-                if (_textMate != null) _textMate.SetGrammar(_registryOptions.GetScopeByExtension(Path.GetExtension(source.FileName)));
+                UpdateGrammar();
                 Text = source.Content;
             }
         }
@@ -101,6 +98,20 @@ namespace SourceGit.Views {
             e.Handled = true;
         }
 
+        private void UpdateGrammar() {
+            if (_textMate == null) return;
+
+            var src = DataContext as Models.RevisionTextFile;
+            if (src == null) return;
+
+            var ext = Path.GetExtension(src.FileName);
+            if (ext == ".h") {
+                _textMate.SetGrammar(_registryOptions.GetScopeByLanguageId("cpp"));
+            } else {
+                _textMate.SetGrammar(_registryOptions.GetScopeByExtension(ext));
+            }
+        }
+
         private RegistryOptions _registryOptions = null;
         private TextMate.Installation _textMate = null;
     }
diff --git a/src/Views/TextDiffView.axaml.cs b/src/Views/TextDiffView.axaml.cs
index 74990a36..69b0ac84 100644
--- a/src/Views/TextDiffView.axaml.cs
+++ b/src/Views/TextDiffView.axaml.cs
@@ -214,10 +214,7 @@ namespace SourceGit.Views {
             }
 
             _textMate = this.InstallTextMate(_registryOptions);
-
-            if (DiffData != null) {
-                _textMate.SetGrammar(_registryOptions.GetScopeByExtension(Path.GetExtension(DiffData.File)));
-            }
+            UpdateGrammar();
         }
 
         protected override void OnUnloaded(RoutedEventArgs e) {
@@ -267,7 +264,7 @@ namespace SourceGit.Views {
                         builder.AppendLine(line.Content);
                     }
 
-                    if (_textMate != null) _textMate.SetGrammar(_registryOptions.GetScopeByExtension(Path.GetExtension(DiffData.File)));
+                    UpdateGrammar();
                     Text = builder.ToString();                    
                 } else {
                     Text = string.Empty;
@@ -281,6 +278,17 @@ namespace SourceGit.Views {
             }
         }
 
+        private void UpdateGrammar() {
+            if (_textMate == null || DiffData == null) return;
+
+            var ext = Path.GetExtension(DiffData.File);
+            if (ext == ".h") {
+                _textMate.SetGrammar(_registryOptions.GetScopeByLanguageId("cpp"));
+            } else {
+                _textMate.SetGrammar(_registryOptions.GetScopeByExtension(ext));
+            }
+        }
+
         private RegistryOptions _registryOptions;
         private TextMate.Installation _textMate;
     }
@@ -497,10 +505,7 @@ namespace SourceGit.Views {
             }
 
             _textMate = this.InstallTextMate(_registryOptions);
-
-            if (DiffData != null) {
-                _textMate.SetGrammar(_registryOptions.GetScopeByExtension(Path.GetExtension(DiffData.File)));
-            }
+            UpdateGrammar();
         }
 
         protected override void OnUnloaded(RoutedEventArgs e) {
@@ -561,7 +566,7 @@ namespace SourceGit.Views {
                         }
                     }
 
-                    if (_textMate != null) _textMate.SetGrammar(_registryOptions.GetScopeByExtension(Path.GetExtension(DiffData.File)));
+                    UpdateGrammar();
                     Text = builder.ToString();
                 } else {
                     Text = string.Empty;
@@ -580,6 +585,17 @@ namespace SourceGit.Views {
             }
         }
 
+        private void UpdateGrammar() {
+            if (_textMate == null || DiffData == null) return;
+
+            var ext = Path.GetExtension(DiffData.File);
+            if (ext == ".h") {
+                _textMate.SetGrammar(_registryOptions.GetScopeByLanguageId("cpp"));
+            } else {
+                _textMate.SetGrammar(_registryOptions.GetScopeByExtension(ext));
+            }
+        }
+
         private RegistryOptions _registryOptions;
         private TextMate.Installation _textMate;
     }