Mixed content on an HTTPS page
What this means
An HTTPS page loads one or more sub-resources over plain HTTP. Browsers block or upgrade much of this, which can break the page; severity rises once more than five resources are affected.
How to fix it
Serve every sub-resource over HTTPS — switch the URLs, use a host that supports TLS, or self-host the asset.
Fix effort
This check needs a developer fix: it turns on a routing, hosting or infrastructure decision that no automatic edit can make safely.
Authoritative source
https://developers.google.com/search/docs/crawling-indexing/site-move-with-url-changes
Find every page this affects
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