diff --git a/src/mobi/hsz/idea/gitignore/IgnoreManager.java b/src/mobi/hsz/idea/gitignore/IgnoreManager.java
index 798f8023..bfd99f16 100644
--- a/src/mobi/hsz/idea/gitignore/IgnoreManager.java
+++ b/src/mobi/hsz/idea/gitignore/IgnoreManager.java
@@ -167,7 +167,7 @@ public void childrenChanged(@NotNull PsiTreeChangeEvent event) {
      * @param project current project
      * @return {@link IgnoreManager instance}
      */
-    public static IgnoreManager getInstance(Project project) {
+    public static IgnoreManager getInstance(@NotNull final Project project) {
         return project.getComponent(IgnoreManager.class);
     }
 
diff --git a/src/mobi/hsz/idea/gitignore/outer/OuterIgnoreWrapper.java b/src/mobi/hsz/idea/gitignore/outer/OuterIgnoreWrapper.java
index 422f9d76..10922358 100644
--- a/src/mobi/hsz/idea/gitignore/outer/OuterIgnoreWrapper.java
+++ b/src/mobi/hsz/idea/gitignore/outer/OuterIgnoreWrapper.java
@@ -93,6 +93,8 @@ public JComponent getComponent() {
 
     @Override
     public void dispose() {
-        EditorFactory.getInstance().releaseEditor(outerEditor);
+        if (outerEditor != null) {
+            EditorFactory.getInstance().releaseEditor(outerEditor);
+        }
     }
 }