Without javascript, the central login check is failing to run correctly.

Local wiki writes an image call that looks something like title=Special:CentralAutoLogin/start&type=1x1&from=enwiki

However, CentralAutoLogin checks for

} elseif( $request->getVal( 'from' ) === wfWikiId() && $wgCentralAuthLoginWiki !== wfWikiId() ) {

Which is true in this case, and so the browser is redirected to the central wiki, to Special:CentralAutoLogin/start, which fails.

The pure javascript version of the check makes a call to:

index.php?title=Special:CentralAutoLogin/start&type=script

So the code above doesn't evaluate true, and everything works.

Version: unspecified
Severity: major