After Neos CMS 5 upgrade: Section "stylesheets" does not exist

Hey :slightly_smiling_face: After upgrade to 5.X I get this error in my combination of Fluid and Fusion

Fluid

<!DOCTYPE html>
{namespace neos=Neos\Neos\ViewHelpers}
{namespace ts=Neos\Fusion\ViewHelpers}
{namespace media=Neos\Media\ViewHelpers}<html>
    <head>
        <f:section name="stylesheets">
            <!-- Put your stylesheet inclusions here, they will be included in your website by TypoScript -->
            <link rel="stylesheet" href="{f:uri.resource(path: 'Libraries/touchscroll/smoothTouchScroll.css', package: 'FDF.Site')}" type="text/css" media="a$
            <link rel="stylesheet" href="{f:uri.resource(path: 'Libraries/jquery-fancybox/jquery.fancybox.css', package: 'FDF.Site')}" type="text/css" media=$
            <link rel="stylesheet" href="{f:uri.resource(path: 'Styles/Site.css', package: 'FDF.Site')}" type="text/css" media="all" />
        </f:section>    </head>

Fusion

page = Neos.Neos:Page {
        head {
                stylesheets.site = Neos.Fusion:Template {
                        templatePath = 'resource://FDF.Site/Private/Templates/Page/Home.html'
                        sectionName = 'stylesheets'
                }

Exception

Exception in line 204 of /var/www/html/Packages/Framework/Neos.FluidAdaptor/Classes/View/AbstractTemplateView.php: Section "stylesheets" does not exist.

44 TYPO3Fluid\Fluid\View\AbstractTemplateView::renderSection("stylesheets", array|2|, false)
43 Neos\FluidAdaptor\View\AbstractTemplateView::renderSection("stylesheets")
42 Neos\Fusion\FusionObjects\TemplateImplementation_Original::evaluate()
41 Neos\Fusion\Core\Runtime_Original::evaluateObjectOrRetrieveFromCache(Neos\Fusion\FusionObjects\TemplateImplementation, "home<Neos.Neos:Page>/head<Neos.Fusion:Array>/stylesheets<Neos.Fusion:Array>/site", array|6|, array|5|)
40 Neos\Fusion\Core\Runtime_Original::evaluate("home<Neos.Neos:Page>/head<Neos.Fusion:Array>/stylesheets<Neos.Fusion:Array>/site", Neos\Fusion\FusionObjects\ArrayImplementation)
39 Neos\Fusion\FusionObjects\AbstractFusionObject::fusionValue("site")
38 Neos\Fusion\FusionObjects\DataStructureImplementation_Original::evaluate()
37 Neos\Fusion\FusionObjects\JoinImplementation_Original::evaluate()
36 Neos\Fusion\Core\Runtime_Original::evaluateObjectOrRetrieveFromCache(Neos\Fusion\FusionObjects\ArrayImplementation, "home<Neos.Neos:Page>/head<Neos.Fusion:Array>/stylesheets", array|5|, array|5|)
35 Neos\Fusion\Core\Runtime_Original::evaluate("home<Neos.Neos:Page>/head<Neos.Fusion:Array>/stylesheets", Neos\Fusion\FusionObjects\ArrayImplementation)
34 Neos\Fusion\FusionObjects\AbstractFusionObject::fusionValue("stylesheets")
33 Neos\Fusion\FusionObjects\DataStructureImplementation_Original::evaluate()
32 Neos\Fusion\FusionObjects\JoinImplementation_Original::evaluate()

the /home path being defined as such

home < page {
    body {
        // Hide breadcrumb menu on home page
        parts {
            breadcrumbMenu >
        }    }}

Don’t mind missing parts of Fusion and Fluid - the relevant parts are cop/pasted and therefore not syntax-correct