add stateSelector to TYPO3 Link

Resources/Public/Plugins/Typo3FileManager/typo3filemanager.js

@@ -116,7 +116,8 @@ var plugin = tinymce.PluginManager.add('typo3filemanager', function(editor, url)
 		title: 'TYPO3 Link',
 		icon: 'link',
 		shortcut: 'Ctrl+K',
-		onclick: openLinkDialog
+		onclick: openLinkDialog,
+		stateSelector: 'a[href]'
 	});
 
 	editor.addButton('typo3image', {
@@ -133,7 +134,8 @@ var plugin = tinymce.PluginManager.add('typo3filemanager', function(editor, url)
 		prependToContext: true,
 		shortcut: 'Ctrl+K',
 		icon: 'link',
-		onclick: openLinkDialog
+		onclick: openLinkDialog,
+		stateSelector: 'a[href]'
 	});
 
 	editor.addMenuItem('typo3image', {