UPGRADING and UPGRADING.INTERNALS for SVG and extensible image API

Author: ndossche

UPGRADING

@@ -245,6 +245,11 @@ PHP 8.5 UPGRADE NOTES
     and the function returns false. Previously, these errors were silently
     ignored. This change affects only the sendmail transport.
 
+- Standard:
+  . getimagesize() now supports SVG images when ext-libxml is also loaded.
+    Similarly, image_type_to_extension() and image_type_to_extension()
+    now also handle IMAGETYPE_SVG.
+
 - XSL:
   . The $namespace argument of XSLTProcessor::getParameter(),
     XSLTProcessor::setParameter() and XSLTProcessor::removeParameter()
@@ -565,6 +570,9 @@ PHP 8.5 UPGRADE NOTES
   . T_VOID_CAST.
   . T_PIPE.
 
+- Standard:
+  . IMAGETYPE_SVG when libxml is loaded.
+
 ========================================
 11. Changes to INI File Handling
 ========================================

UPGRADING.INTERNALS

@@ -134,6 +134,10 @@ PHP 8.5 INTERNALS UPGRADE NOTES
   . The php_std_date() function has been removed. Use php_format_date() with
     the "D, d M Y H:i:s \\G\\M\\T" format instead.
   . Added php_url_encode_to_smart_str() to encode a URL to a smart_str buffer.
+  . The functionality of getimagesize(), image_type_to_mime_type(),
+    and image_type_to_extension() is now extensible using the internal APIs
+    php_image_register_handler() and php_image_unregister_handler() in
+    php_image.h.
 
 ========================
 4. OpCode changes