diff --git a/src/NUglify.Tests/JavaScript/Bugs.cs b/src/NUglify.Tests/JavaScript/Bugs.cs
index dda5105e..5372bf4d 100644
--- a/src/NUglify.Tests/JavaScript/Bugs.cs
+++ b/src/NUglify.Tests/JavaScript/Bugs.cs
@@ -170,6 +170,13 @@ public void Bug189()
 	        TestHelper.Instance.RunTest("-pretty -comments:all");
         }
 
+
+        [Test]
+        public void Bug189Important()
+        {
+	        TestHelper.Instance.RunTest("-pretty -comments:important");
+        }
+
         [Test]
         public void Bug197()
         {
diff --git a/src/NUglify.Tests/NUglify.Tests.csproj b/src/NUglify.Tests/NUglify.Tests.csproj
index 758527eb..095ed992 100644
--- a/src/NUglify.Tests/NUglify.Tests.csproj
+++ b/src/NUglify.Tests/NUglify.Tests.csproj
@@ -476,6 +476,9 @@
     <Content Include="TestData\JS\Expected\Bugs\Bug241.js">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
+    <Content Include="TestData\JS\Expected\Bugs\Bug189Important.js">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
     <Content Include="TestData\JS\Expected\Bugs\Bug197.js">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
@@ -501,7 +504,7 @@
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
     <Content Include="TestData\JS\Expected\Bugs\Bug189.js">
-	    <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
     <Content Include="TestData\JS\Expected\Bugs\Bug199JSON.js">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
@@ -2842,6 +2845,9 @@
     <Content Include="TestData\JS\Input\Bugs\Bug293.js">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
+    <Content Include="TestData\JS\Input\Bugs\Bug189Important.js">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
     <Content Include="TestData\JS\Input\Bugs\Bug279.js">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
diff --git a/src/NUglify.Tests/TestData/JS/Expected/Bugs/Bug189.js b/src/NUglify.Tests/TestData/JS/Expected/Bugs/Bug189.js
index 4097c06a..3282d162 100644
--- a/src/NUglify.Tests/TestData/JS/Expected/Bugs/Bug189.js
+++ b/src/NUglify.Tests/TestData/JS/Expected/Bugs/Bug189.js
@@ -1,4 +1,8 @@
 let x = 1
 // a comment
 // another comment
+//! important comment
+/*!
+	another important comment
+ */;
 let y = 2
diff --git a/src/NUglify.Tests/TestData/JS/Expected/Bugs/Bug189Important.js b/src/NUglify.Tests/TestData/JS/Expected/Bugs/Bug189Important.js
new file mode 100644
index 00000000..230f3b95
--- /dev/null
+++ b/src/NUglify.Tests/TestData/JS/Expected/Bugs/Bug189Important.js
@@ -0,0 +1,6 @@
+let x = 1
+//! important comment
+/*!
+	another important comment
+ */;
+let y = 2
diff --git a/src/NUglify.Tests/TestData/JS/Input/Bugs/Bug189.js b/src/NUglify.Tests/TestData/JS/Input/Bugs/Bug189.js
index ee5fcf3e..9e4e66ec 100644
--- a/src/NUglify.Tests/TestData/JS/Input/Bugs/Bug189.js
+++ b/src/NUglify.Tests/TestData/JS/Input/Bugs/Bug189.js
@@ -1,3 +1,7 @@
 let x = 1; // a comment
 // another comment
+//! important comment
+/*!
+	another important comment
+ */
 let y = 2;
diff --git a/src/NUglify.Tests/TestData/JS/Input/Bugs/Bug189Important.js b/src/NUglify.Tests/TestData/JS/Input/Bugs/Bug189Important.js
new file mode 100644
index 00000000..9e4e66ec
--- /dev/null
+++ b/src/NUglify.Tests/TestData/JS/Input/Bugs/Bug189Important.js
@@ -0,0 +1,7 @@
+let x = 1; // a comment
+// another comment
+//! important comment
+/*!
+	another important comment
+ */
+let y = 2;