The RadEditor's Media Manager dialog uses pasteHtml functionality to insert Object elements in the contentArea. The pasteHtml functionality do not position the cursor correctly for this case (pasted content ends with a object).

The issue can be workarounded by appending a character after the object. Then using a content filter the additional characters will be removed.

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

<script type="text/javascript">
	function OnClientPasteHtml(editor, args) {
		if ($telerik.isChrome && args.get_commandName() == "MediaManager") {
			args.set_value(args.get_value() + String.fromCharCode(8203));
		}
	}

	function OnClientLoad(editor, args) {
		if ($telerik.isChrome) {
			editor.get_filtersManager().add(new MyFilter());
		}
	}

	MyFilter = function() {
		MyFilter.initializeBase(this);
		this.set_isDom(false);
		this.set_enabled(true);
		this.set_name("RadEditor filter");
		this.set_description("RadEditor filter description");
	}
	MyFilter.prototype =
	{
		getHtmlContent: function(content) {
			return content.replace(/(object>)[\u200b]/gm, "$1"); // or content.replace(/[\u200b]/gm, "")
		},
		getDesignContent: function(content) {
			return content;
		}
	}
	MyFilter.registerClass('MyFilter', Telerik.Web.UI.Editor.Filter);
</script>