One thing I'm not sure about - is it appropriate to return false for fail from onSubmit? The docs for that method say:

@return Bool|Array true for success, false for didn't-try, array of errors on failure

I'm not sure if hook arborted should be error instead of "didn't try".

As a note, in my testing, things are still slightly different because something like (stolen from bug report):

$wgHooks['ArticlePurge'][] = 'testArticlePurge';
 function testArticlePurge( &$article ) {
    global $wgOut;
    $wgOut->addWikiMsg( 'error' );
    return false;
}

Would present an error page with no page title (in the

) in 1.17, but now would use the page's title in the

. However, I don't think that's something to really care about.

I swear I escaped that with entities. Try 2:

One thing I'm not sure about - is it appropriate to return false for fail from onSubmit? The docs for that method say:

@return Bool|Array true for success, false for didn't-try, array of errors on failure

I'm not sure if hook arborted should be error instead of "didn't try".

As a note, in my testing, things are still slightly different because something like (stolen from bug report):

$wgHooks['ArticlePurge'][] = 'testArticlePurge';

function testArticlePurge( &$article ) {
   global $wgOut;
   $wgOut->addWikiMsg( 'error' );
   return false;

}

Would present an error page with no page title (in the < h1 >) in 1.17, but now would use the page's title in the < h1 > . However, I don't think that's something to really care about.