Googles testing tool for structured data (https://search.google.com/structured-data/testing-tool) gives an error on the "root" page because "itemListElement" is empty. I think the output of an empty breadcrump should be omitted.
My suggestion would be to add a typoscript condition "[tree.level > 0]" within "Configuration/TypoScript/Setup/structuredData.typoscript" around "page.footerData.656".
Or you could add a condition
if (count($rootline) < 2) { return ''; }
in "Classes/UserFunc/StructuredData.php" after line 117.
Googles testing tool for structured data (https://search.google.com/structured-data/testing-tool) gives an error on the "root" page because "itemListElement" is empty. I think the output of an empty breadcrump should be omitted.
My suggestion would be to add a typoscript condition "[tree.level > 0]" within "Configuration/TypoScript/Setup/structuredData.typoscript" around "page.footerData.656".
Or you could add a condition
if (count($rootline) < 2) { return ''; }
in "Classes/UserFunc/StructuredData.php" after line 117.