Since eZ Publish Fuji, the "Extension Ordering" mechanism enables extensions to define in which order they should be loaded in regards to other, related, extensions. The function is very usefull to manage the loading order of templates and settings from extensions.

cf. http://doc.ez.no/eZ-Publish/Technical-manual/4.6/Installation/Extensions/Extension-load-ordering

But the mechanism doesn't work with ActiveAccessExtension activated within siteaccesses.

For example :
I have an multisite eZ Publish instance with :

• A global extension "backend", activated in settings/override/site.ini.append.php, and having default settings
• A specific extension for site A, activated in settings/siteaccess/site_a/site.ini.append.php, and overriding some settings
• Another specitic extension for site B, activated in settings/siteaccess/site_b/site.ini.append.php, and overriding some other settings

I cannot use ExtensionOrdering and extension.xml files to use extension A (or extension B) settings instead of backend settings.

Steps to reproduce

Create an eZ Publish instance, with joined files (extensions + settings).

Go to http://a.mysite.loc

=> You will see the text "extension A" (TestSettings/Extension from extension A), it's OK

Now, edit settings :
settings/override/site.ini.append.php : comment line "ActiveExtensions[]=extension_a"
settings/siteaccess/site_a/site.ini.append.php : uncomment line "#ActiveAccessExtensions[]=site_a"

Empty caches and reload the page http://a.mysite.loc

=> You will see the text "backend" (TestSettings/Extension from backend), while we wanted to keep settings from "extension A"