tribute.
editor.setData( '&lt;p <strong>style="color: red"</strong>&gt;Hello <strong>&lt;em&gt;world&lt;/em&gt;</strong>!&lt;/p&gt;' );
alert( editor.getData() );

// Filtered data is returned.
"&lt;p&gt;Hello world!&lt;/p&gt;"
</pre>
		<p>
			What happened? Since <code>config.allowedContent: 'p'</code> is set the editor assumes
			that only plain <code>&lt;p&gt;</code> are accepted. Nothing more. This is why
			<code>style</code> attribute and <code>&lt;em&gt;</code> tag are gone. The same
			filtering would happen if we pasted disallowed HTML into this editor.
		</p>
		<p>
			This is just a small sample of what <abbr title="Advanced Content Filter">ACF</abbr>
			can do. To know more, please refer to the sample section below and
			<a href="https://docs.ckeditor.com/ckeditor4/docs/#!/guide/dev_advanced_content_filter">the official Advanced Content Filter guide</a>.
		</p>
		<p>
			You may, of course, want CKEditor to avoid filtering of any kind.
			To get rid of <abbr title="Advanced Content Filter">ACF</abbr>,
			basically set <code><a class="samples"
			href="https://docs.ckeditor.com/ckeditor4/docs/#!/api/CKEDITOR.config-cfg-allowedContent">
			config.allowedContent</a></code> to <code>true</code> like this:
		</p>
<pre class="samples">
CKEDITOR.replace( <em>textarea_id</em>, {
	<strong>allowedContent: true</strong>
} );
</pre>

		<h2>Beyond data flow: Features activation</h2>
		<p>
			<abbr title="Advanced Content Filter">ACF</abbr> is far more than
			<abbr title="Input/Output">I/O</abbr> control: the entire
			<abbr title="User Interface">UI</abbr> of the editor is adjusted to what
			filters restrict. For example: if <code>&lt;a&gt;</code> tag is
			<strong>disallowed</strong>
			by <abbr title="Advanced Content Filter">ACF</abbr>,
			then accordingly <code>link</code> command, toolbar button and link dialog
			are also disabled. Editor is smart: it knows which features must be
			removed from the interface to match filtering rules.
		</p>
		<p>
			CKEditor can be far more specific. If <code>&lt;a&gt;</code> tag is
			<strong>allowed</strong> by filtering rules to be used but it is restricted
			to have only one attribute (<code>href</code>)
			<code>config.allowedContent = 'a[!href]'</code>, then
			"Target" tab of the link dialog is automatically disabled as <code>target</code>
			attribute isn't included in <abbr title="Advanced Content Filter">ACF</abbr> rules
			for <code>&lt;a&gt;</code>. This behaviour applies to dialog fields, context
			menus and toolbar buttons.
		</p>

		<h2>Sample configurations</h2>
		<p>
			There are several editor instances below that present different
			<abbr title="Advanced Content Filter">ACF</abbr> setups. <strong>All of them,
			except the inline instance, share the same HTML content</strong> to visualize
			how different filtering rules affect the same input data.
		</p>
	</div>

	<div>
		<label for="editor1">
			Editor 1:
		</label>
		<div class="description">
			<p>
				This editor is using default configuration ("automatic mode"). It means that
				<code><a class="samples"
				href="https://docs.ckeditor.com/ckeditor4/docs/#!/api/CKEDITOR.config-cfg-allowedContent">
				config.allowedContent</a></code> is defined by loaded plugins.
				Each plugin extends filtering rules to make it's own associated content
				available for the user.
			</p>
		</div>
		<textarea cols="80" id="editor1" name="editor1" rows="10">
			&lt;h1&gt;&lt;img alt=&quot;Saturn V carrying Apollo 11&quot; class=&quot;right&quot; src=&quot;assets/sample.jpg&quot;/&gt; Apollo 11&lt;/h1&gt; &lt;p&gt;&lt;b&gt;Apollo 11&lt;/b&gt; was the spaceflight that landed the first humans, Americans &lt;a href=&quot;http://en.wikipedia.org/wiki/Neil_Armstrong&quot; title=&quot;Neil Armstrong&quot;&gt;Neil Armstrong&lt;/a&gt; and &lt;a href=&quot;http://en.wikipedia.org/wiki/Buzz_Aldrin&quot; title=&quot;Buzz Aldrin&quot;&gt;Buzz Aldrin&lt;/a&gt;, on the Moon on July 20, 1969, at 20:18 UTC. Armstrong became the first to step onto the lunar surface 6 hours later on July 21 at 02:56 UTC.&lt;/p&gt; &lt;p&gt;Armstrong spent about &lt;s&gt;three and a half&lt;/s&gt; two and a half hours outside the spacecraft, Aldrin slightly less; and together they c