132889 [Browser] DefaultBrowserSupport.createBrowser() creates a new one even a browser with the same browserID is already open
diff --git a/bundles/org.eclipse.ui.browser/src/org/eclipse/ui/internal/browser/BrowserManager.java b/bundles/org.eclipse.ui.browser/src/org/eclipse/ui/internal/browser/BrowserManager.java
index 0343373..987967b 100644
--- a/bundles/org.eclipse.ui.browser/src/org/eclipse/ui/internal/browser/BrowserManager.java
+++ b/bundles/org.eclipse.ui.browser/src/org/eclipse/ui/internal/browser/BrowserManager.java
@@ -47,8 +47,10 @@
 				if (!ignorePreferenceChanges && property.equals("browsers")) { //$NON-NLS-1$
 					loadBrowsers();
 				}
-				setChanged();
-				notifyObservers();
+				if (!property.equals(WebBrowserPreference.PREF_INTERNAL_WEB_BROWSER_HISTORY)) {
+					setChanged();
+					notifyObservers();
+				}
 			}
 		};