Entering two consecutive spaces in the middle of a paragraph causes the cursor to jump to the end of the paragraph.

The issue is reproducible with version 2015.1.401 (and not reproducible with Q3 2014)

Steps to reproduce:
1. Open the following url in IE11, setting the compatibility mode to IE8 (or in real IE8)
2. Type in a short sentence into the Editor
3. Place the cursor in the middle sentence and hit the space bar (or other char inserting button)  twice

Result: The cursor will jumps to the end of the sentence.

Due to this behavior the font name applied is getting cleared when switching to HTML mode.

The Rad Editor control removes unformatted spaces between differently-formatted words when the user presses Enter key for the first time in IE

Steps to reproduce:
    1. Go to http://demos.telerik.com/aspnet-ajax/editor/examples/overview/defaultcs.aspx and clear all the pre-existing text.
    2. In the empty editing area, type two words separated by a space.
    3. Select the first word but not the space after it, and apply either italics, boldness, or underlining.
    4. Select the second word but not the space before it, and apply a different one of those formatting options.
    5. Position the cursor at the end of the line, and press Enter

Result: The space between the words will vanish. Firefox users will see underlining indicating that the browser considers the new, merged word to be misspelled.

The following commands does not work with the Format Painter tool.

   1. underline 
   2. strikethrough 
   3. back color
   4. fore color
   5. bold

When this is happening the editor is unavailable for editing and the button for disabling this mode is also unavailable.

A possible resolution is to use the Form Template option of the EditFormSettings property and set a RadEditor control with the following function attached to the OnClientCommandExecuted event:

function OnClientCommandExecuted(editor, args) {
	var commandName = args.get_commandName();
	if (commandName === "ToggleScreenMode") {
		var isFullScreen = editor.isFullScreen();
		var modalExtender = $telerik.$("#modalDivId_<%= RadGrid1.ClientID %>");

		if (isFullScreen)
			modalExtender.hide();
		else
			modalExtender.show();
		}
	}


Also, this happens with simple DOM elements set with fixed position. The following workaround fixes the Full Screen of  the RadEditor control in all similar cases when elements are overlaying. 

<telerik:RadEditor runat="server" ID="RE1" OnClientCommandExecuted="OnClientCommandExecuted">
</telerik:RadEditor>

<script type="text/javascript">
	function OnClientCommandExecuted(editor, args) {
		if (args.get_commandName() === "ToggleScreenMode") {
			var editorElement = editor.get_element();
			if (editor.isFullScreen()) {
				editorElement.style.position = "absolute";
				editorElement.style.zIndex = "100000";
			} else {
				editorElement.style.position = "";
				editorElement.style.zIndex = "";
			}
		}
	}
</script>

When the Toggle Full Screen is pressed the RadEditor does not fill the entire page.

If the content contains html, head and body tags (Full HTML editing), and switching to Design mode causes a slightly slower rendering.

If the same HTML is used directly in the, the design mode renders as expected.

When RadEditor is disabled from the client-side (enableEditing and set_editable are set to false) the user is still allowed to indent the content using the Tab key in Internet Explorer. 

Workaround:
<telerik:RadTabStrip ID="RadTabStrip1" runat="server" MultiPageID="RadMultiPage1">
	<Tabs>
		<telerik:RadTab Text="tab1" Selected="true"></telerik:RadTab>
		<telerik:RadTab Text="tab2"></telerik:RadTab>
	</Tabs>
</telerik:RadTabStrip>
<telerik:RadMultiPage ID="RadMultiPage1" runat="server">
	<telerik:RadPageView ID="RadPageView1" runat="server" Selected="true">RadPageView 1</telerik:RadPageView>
	<telerik:RadPageView ID="RadPageView2" runat="server">
		<telerik:RadEditor ID="RadEditor1" runat="server" EnableTrackChanges="true"
			TrackChangesSettings-CanAcceptTrackChanges="true" ToolsFile="ToolsTrackChanges.xml">
			<Content>
				<p>paragraph 1</p>
				<p>paragraph 2</p>
			</Content>
		</telerik:RadEditor>

	</telerik:RadPageView>
</telerik:RadMultiPage>

<script type="text/javascript">
	$telerik.$.extend(Telerik.Web.UI.RadEditor.prototype, {
		_initEvents: function() {
			var editor = this;
			if (editor.__original__initEvents) {
				editor.__original__initEvents();
			}
			editor.add_domChange(Function.createDelegate(editor, editor._domChangedHandler));
			editor.attachInternalHandler("keypress", Function.createDelegate(editor, editor._keyPressHandler));
			editor.attachInternalHandler("keydown", Function.createDelegate(editor, editor._keyDownHandlerEnableTrackChangesOverride));
			editor.attachInternalHandler("keydown", Function.createDelegate(editor, editor._keyDownHandler));
		}
	});
</script>

When using the built-in AJAX Spell Checker of the Editor, on the first misspelled word the corresponding popup opens. 

When the user finishes with the first word, the same popup should open for the following word, but under IE11 this does not happen and the user is forced to click on the word for the dialog to open.

To resolve this you can force the IE11 browser to IE10 compatibility mode with a meta tag in the head element pf the page

<meta http-equiv="X-UA-Compatible" content="IE=10" />

When typing text, user tries to change the font-size or font-name a span element is added into the content with the chosen formatting options, but new text is not added into the span but outside.

Due to that the applied formatting does not affect the new text typed in the RadEditor. 

The first div element in the content is stripped out, every time a submit occurs with opened HTML tab.

Feature request for implementing an improvement related to the current impossibility to select form elements like buttons in RadEditor content area. This is a browser behavior and it is currently preventing form editing element's properties in the module manager.

In this scenario the EncodeScripts and RemoveScripts filters are disabled, so that script tags can be inserted. Using a script tag with some HTML content after it and submit when still on HTML mode, the content after the script tag will be removed. 

For the time being you can workaround this problem by forcing the editor to switch to Design mode on submitting:

<telerik:RadEditor ID="RadEditor2" runat="server" OnClientSubmit="OnClientSubmit">
</telerik:RadEditor>

<script>
    function OnClientSubmit(sender, args) {
        sender.set_mode(Telerik.Web.UI.EditModes.Design);
    }
</script>

Using the Hyperlink manager in a RibbonBar toolbar, causes the selection to be lost. By that, adding a hyperlink to an image, the link is inserted to the content, but it does not wrap the image element.

The behavior is different across IE versions. Under IE11, the link seems to disappear.

This may result in invalid content being sent to the server or incorrect behavior of the client-side.

The described issue is because of the "Zero width nbsp" character, which is not stripped when the text is submitted. 

Possible resolution is to strip the character with custom function attached to the OnClientSubmit event of the RadEditor control:

<telerik:RadEditor runat="server" ID="RadEditor1" 
    OnClientSubmit="OnClientSubmit" />

<script type="text/javascript">
	function OnClientSubmit(editor, args) {
		
		var html = editor.get_html(true);
		html = html.replace(/\u200b/g, "");
		editor.set_html(html);
	}
</script>

There some issues when both features are enabled:

    - Add comment to tracked change is impossible;
    - Context menu is broken.

For the time being you can use either approach:

1) Disable ConvertToXhtml filter:

C#:

    protected void Page_Load(object sender, EventArgs e)
    {
        RadEditor1.DisableFilter(EditorFilters.ConvertToXhtml);
    }
ASPX:

        <telerik:RadEditor ID="RadEditor1" runat="server">
            <Content>
            <p>  <h2></h2>  <h2></h2>  </p>
            </Content>
        </telerik:RadEditor>
        <script type="text/javascript">
            Telerik.Web.UI.Editor.NestedElementsFix.prototype._shouldRemoveBlockElement = function (element, elementChanged) {
                var utils = Telerik.Web.UI.Editor.Utils;
                if (!elementChanged || !element) return false;
                if (!/^li|td|th$/.test(element.nodeName) &&
                    utils.isNodeEmptyRecursive(element) &&
                    !$telerik.$(element).find("ol,ul,table,h1,h2,h3,h4,h5,h6").length) {
                    return true;
                }
                return false;
            }
        </script>