8
Compliance is not a matter of percentages. You do have it or you do not.
In the years that XOOPS exists, standards have been shifted and to bridge the gap, there are transitional standards too.
The core is designed to be compliant, but a lot of themes and modules do not comply with the latest standards (or even not with the older ones). And then there is also the user which can add in WYSIWYG editors html content, which may also be a source of non-compliance.
So, altough designed and intented to, XOOPS may not be compliant.
You can check the compliance with the
W3C validator. If you run it for this
thread, my check found 183 errors (altough a lot are structured doubles and when you fix 1 error, you fix a lot).
To know if a site is compliant, all pages must be compliant and that means passing the test for all occurences and combinations.
Many sites
label themselves as W3C compliant, but in reality only a few small and static sites pass the test. Read all about the Markup Validition in this
FAQ.