diff --git a/TODO b/TODO
index e19a2ed5..b25cf9fc 100644
--- a/TODO
+++ b/TODO
@@ -12,6 +12,11 @@ amount of effort to implement, it may get endlessly delayed. Do not be
 afraid to cast your vote for the next feature to be implemented!
 
 - Implement validation for query and for fragment
+- Allow imagecrash protection in CSS images to be turned off
+- Allow imagecrash protection in CSS to be configurable with a max value
+- Maintain old attribute data in tokens (configurable?)
+- Allow URIFilters to run early?
+- Lazy update of token when validating attributes?
 
 FUTURE VERSIONS
 ---------------
diff --git a/library/HTMLPurifier.includes.php b/library/HTMLPurifier.includes.php
index 8060b49f..d22ed07d 100644
--- a/library/HTMLPurifier.includes.php
+++ b/library/HTMLPurifier.includes.php
@@ -52,6 +52,7 @@ require 'HTMLPurifier/IDAccumulator.php';
 require 'HTMLPurifier/Injector.php';
 require 'HTMLPurifier/Language.php';
 require 'HTMLPurifier/LanguageFactory.php';
+require 'HTMLPurifier/Length.php';
 require 'HTMLPurifier/Lexer.php';
 require 'HTMLPurifier/PercentEncoder.php';
 require 'HTMLPurifier/Strategy.php';
@@ -66,6 +67,7 @@ require 'HTMLPurifier/URIFilter.php';
 require 'HTMLPurifier/URIParser.php';
 require 'HTMLPurifier/URIScheme.php';
 require 'HTMLPurifier/URISchemeRegistry.php';
+require 'HTMLPurifier/UnitConverter.php';
 require 'HTMLPurifier/VarParser.php';
 require 'HTMLPurifier/VarParserException.php';
 require 'HTMLPurifier/AttrDef/CSS.php';
diff --git a/library/HTMLPurifier.safe-includes.php b/library/HTMLPurifier.safe-includes.php
index 4273da36..32930c0a 100644
--- a/library/HTMLPurifier.safe-includes.php
+++ b/library/HTMLPurifier.safe-includes.php
@@ -46,6 +46,7 @@ require_once $__dir . '/HTMLPurifier/IDAccumulator.php';
 require_once $__dir . '/HTMLPurifier/Injector.php';
 require_once $__dir . '/HTMLPurifier/Language.php';
 require_once $__dir . '/HTMLPurifier/LanguageFactory.php';
+require_once $__dir . '/HTMLPurifier/Length.php';
 require_once $__dir . '/HTMLPurifier/Lexer.php';
 require_once $__dir . '/HTMLPurifier/PercentEncoder.php';
 require_once $__dir . '/HTMLPurifier/Strategy.php';
@@ -60,6 +61,7 @@ require_once $__dir . '/HTMLPurifier/URIFilter.php';
 require_once $__dir . '/HTMLPurifier/URIParser.php';
 require_once $__dir . '/HTMLPurifier/URIScheme.php';
 require_once $__dir . '/HTMLPurifier/URISchemeRegistry.php';
+require_once $__dir . '/HTMLPurifier/UnitConverter.php';
 require_once $__dir . '/HTMLPurifier/VarParser.php';
 require_once $__dir . '/HTMLPurifier/VarParserException.php';
 require_once $__dir . '/HTMLPurifier/AttrDef/CSS.php';