Small recommendation that has saved me a few times: run any schema change through Google’s Rich Results Test before deploying.
– Tells you if the page is eligible for rich results (product, FAQ, breadcrumb etc)
– Shows errors vs warnings clearly
– You can test a code snippet directly, not just a live URL
Free and quick. Validators that only check syntax don’t tell you what Google will actually use.
Also the Schema Markup Validator (schema.org one) catches syntax stuff that the Rich Results Test ignores because it only checks rich-result types. I use both.
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