Originally:
$wgOut->addLink( [ 'rel' => 'stylesheet', 'href' => "$wgScriptPath/extensions/SecurePoll/resources/SecurePoll.css", 'type' => 'text/css' ] ); $wgOut->addScriptFile( "$wgScriptPath/extensions/SecurePoll/resources/SecurePoll.js" );
The CSS has been moved to RL, the JS is harder though (see comments below)
Current state of affairs:
$out->addModuleStyles( 'ext.securepoll.special' ); $out->addScriptFile( "$wgExtensionAssetsPath/SecurePoll/resources/SecurePoll.js" );