Javadoc Hover suddenly broke in eclipse luna - eclipse

Question

I installed eclipse luna a week ago and worked every day with it until the javadoc broke yesterday.
When i hover on a class or method, the popup shows, with the right dimension apparently, but it's blank.
This problem happens for classes that i wrote, classes that come from maven dependencies and classes from the jdk (like String).
I restarted eclipse, the computer, and it still doesn't work.
I didn't notice anything i did diferently that could have caused this.
I looked at the build path and for each jar, there is the source path and the javadoc path.
The javadoc view is empty also.
I don't know what to do. I can't work without the javadoc hovers.
Edit :
In the error view i saw that the first time i try to hover i get an Internal error on "org.eclipse.jdt.ui" :
java.net.MalformedURLException: unknown protocol: res
at java.net.URL.<init>(Unknown Source)
at java.net.URL.<init>(Unknown Source)
at java.net.URL.<init>(Unknown Source)
at org.eclipse.jdt.internal.ui.viewsupport.JavaElementLinks$1.changing(JavaElementLinks.java:300)
at org.eclipse.swt.browser.IE$7.handleEvent(IE.java:510)
at org.eclipse.swt.ole.win32.OleEventTable.sendEvent(OleEventTable.java:55)
at org.eclipse.swt.ole.win32.OleEventSink.notifyListener(OleEventSink.java:152)
at org.eclipse.swt.ole.win32.OleEventSink.Invoke(OleEventSink.java:120)
at org.eclipse.swt.ole.win32.OleEventSink.access$1(OleEventSink.java:97)
at org.eclipse.swt.ole.win32.OleEventSink$1.method6(OleEventSink.java:71)
at org.eclipse.swt.internal.ole.win32.COMObject.callback6(COMObject.java:119)
at org.eclipse.swt.internal.win32.OS.DispatchMessageW(Native Method)
at org.eclipse.swt.internal.win32.OS.DispatchMessage(OS.java:2549)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3759)
at org.eclipse.jface.internal.text.html.BrowserInformationControl.setVisible(BrowserInformationControl.java:351)
at org.eclipse.jface.text.AbstractInformationControlManager.showInformationControl(AbstractInformationControlManager.java:1270)
at org.eclipse.jface.text.TextViewerHoverManager.showInformationControl(TextViewerHoverManager.java:283)
at org.eclipse.jface.text.AbstractInformationControlManager.internalShowInformationControl(AbstractInformationControlManager.java:1221)
at org.eclipse.jface.text.AbstractInformationControlManager.presentInformation(AbstractInformationControlManager.java:1150)
at org.eclipse.jface.text.AbstractHoverInformationControlManager.presentInformation(AbstractHoverInformationControlManager.java:902)
at org.eclipse.jface.text.TextViewerHoverManager.doPresentInformation(TextViewerHoverManager.java:243)
at org.eclipse.jface.text.TextViewerHoverManager$5.run(TextViewerHoverManager.java:233)
at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:136)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4147)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3764)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$9.run(PartRenderingEngine.java:1151)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1032)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:148)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:636)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:579)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:135)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:382)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:236)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:648)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:603)
at org.eclipse.equinox.launcher.Main.run(Main.java:1465)
Edit 2 : it still doesn't work !
I uninstalled eclipse and reinstalled a fresh one, i wiped the workspace, there are no changes.

Answer 1

The problem is as the #Pavel Horal said
You should switch your browser to a different one , the default browser is IE by modifying the eclipse.ini file eclipse.org/swt/faq.php#browserspecifydefault
or just add
-Dorg.eclipse.swt.browser.DefaultType=mozilla
at the end of your eclipse.ini file.
Or if you are more comfortable with UI interface of the eclipse you can use this help to change the default browser HELP.