silverstripe-framework/admin/templates/Includes/LeftAndMain_EditForm.ss

<% if IncludeFormTag %>
<form $FormAttributes data-layout="{type: 'border'}">
<% end_if %>
	<div class="cms-content-header north">
		<div>
			<h2 id="page-title-heading">
			<% control Controller %>
				<% include CMSBreadcrumbs %>
			<% end_control %>
			</h2>
			<% if Fields.hasTabset %>
				<% with Fields.fieldByName('Root') %>
				<div class="cms-content-header-tabs">
					<ul>
					<% control Tabs %>
						<li><a href="#$id">$Title</a></li>
					<% end_control %>
					</ul>
				</div>
				<% end_with %>
			<% end_if %>
	
			<!-- <div class="cms-content-search">...</div> -->
		</div>
	</div>
	
	<% if Tools %>
		<div class="cms-content-tools west cms-panel cms-panel-layout collapsed" id="cms-content-tools" data-expandOnClick="true" data-layout="{type: 'border'}">
			$Tools
		</div>
	<% end_if %>
	
	<div class="center cms-panel-layout" id="center-container-here" data-layout="{type: 'border'}">
		<div class="cms-content-fields center">
			<% if Message %>
			<p id="{$FormName}_error" class="message $MessageType">$Message</p>
			<% else %>
			<p id="{$FormName}_error" class="message $MessageType" style="display: none"></p>
			<% end_if %>

			<fieldset>
				<% if Legend %><legend>$Legend</legend><% end_if %> 
				<% control Fields %>
					$FieldHolder
				<% end_control %>
				<div class="clear"><!-- --></div>
			</fieldset>
		</div>

		<div class="cms-content-actions south">
			<% if Actions %>
			<div class="Actions">
				<% control Actions %>
					$Field
				<% end_control %>
				<% if CurrentPage.PreviewLink %>
				<a href="$CurrentPage.PreviewLink" class="cms-preview-toggle-link ss-ui-button">
					<% _t('LeftAndMain.PreviewButton', 'Preview') %> &raquo;
				</a>
				<% end_if %>
			</div>
			<% end_if %>
		</div>
	</div>
<% if IncludeFormTag %>
</form>
<% end_if %>