diff --git a/code/controllers/CMSPageAddController.php b/code/controllers/CMSPageAddController.php
index aa34269c..2110d009 100644
--- a/code/controllers/CMSPageAddController.php
+++ b/code/controllers/CMSPageAddController.php
@@ -20,7 +20,7 @@ class CMSPageAddController extends CMSPageEditController {
 		$pageTypes = array();
 		foreach($this->PageTypes() as $type) {
 			$html = sprintf('<span class="page-icon class-%s"></span><strong class="title">%s</strong><span class="description">%s</span>',
-				$type->getField('ClassName'),
+				Convert::raw2htmlid($type->getField('ClassName')),
 				$type->getField('AddAction'),
 				$type->getField('Description')
 			);
diff --git a/code/controllers/LeftAndMainPageIconsExtension.php b/code/controllers/LeftAndMainPageIconsExtension.php
index ffa74ec2..43a4174f 100644
--- a/code/controllers/LeftAndMainPageIconsExtension.php
+++ b/code/controllers/LeftAndMainPageIconsExtension.php
@@ -33,12 +33,7 @@ class LeftAndMainPageIconsExtension extends Extension {
 			// Legacy support: Add file extension if none exists
 			if(!pathinfo($iconFile, PATHINFO_EXTENSION)) $iconFile .= '-file.gif';
 
-			$iconPathInfo = pathinfo($iconFile);
-			
-			// Base filename
-			$baseFilename = $iconPathInfo['dirname'] . '/' . $iconPathInfo['filename'];
-			$fileExtension = $iconPathInfo['extension'];
-
+			$class = Convert::raw2htmlid($class);
 			$selector = ".page-icon.class-$class, li.class-$class > a .jstree-pageicon";
 
 			if(Director::fileExists($iconFile)) {
diff --git a/code/model/SiteTree.php b/code/model/SiteTree.php
index d4082f99..e8f6b8cb 100755
--- a/code/model/SiteTree.php
+++ b/code/model/SiteTree.php
@@ -2830,7 +2830,8 @@ class SiteTree extends DataObject implements PermissionProvider,i18nEntityProvid
 		}
 		$flags = $this->getStatusFlags();
 		$treeTitle = sprintf(
-			"<span class=\"jstree-pageicon\"></span><span class=\"item\" data-allowedchildren=\"%s\">%s</span>",
+			"<span class=\"jstree-pageicon page-icon class-%s\"></span><span class=\"item\" data-allowedchildren=\"%s\">%s</span>",
+			Convert::raw2htmlid($this->class),
 			Convert::raw2att(Convert::raw2json($children)),
 			Convert::raw2xml(str_replace(array("\n","\r"),"",$this->MenuTitle))
 		);
@@ -2883,7 +2884,7 @@ class SiteTree extends DataObject implements PermissionProvider,i18nEntityProvid
 	 * @return string
 	 */
 	public function CMSTreeClasses($numChildrenMethod="numChildren") {
-		$classes = sprintf('class-%s', $this->class);
+		$classes = sprintf('class-%s', Convert::raw2htmlid($this->class));
 		if($this->HasBrokenFile || $this->HasBrokenLink) {
 			$classes .= " BrokenLink";
 		}