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You can index external website using Azure Cognitive Search indexing too.
There are also several solutions available in the Azure Marketplace that can help you scrape content from a website URL. One such solution is the "Web Data Connector" by DataChant, which is a Power BI custom connector that allows you to extract data from web pages and import it into Power BI.
Another solution is the "Web Scraping" solution by Scrapinghub, which is a cloud-based web scraping platform that allows you to extract data from websites at scale.
Once saved to blob storage, you can create indexes out of it, but please make sure to preprocess scraped data from URL so that it can be indexed properly.
Reference thread: external-webs
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