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Manual Accessibility Testing from web.dev is a great intro to manual testing in general.
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InfluxDB
Purpose built for real-time analytics at any scale. InfluxDB Platform is powered by columnar analytics, optimized for cost-efficient storage, and built with open data standards.
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I really like the suggestions from other commenters here, WAVE, Axe, and Google Lighthouse are great automated tools. I'd also recommend SiteImprove and Microsoft's Accessibility Insights for their automated offerings. I have some further suggestions should you also want to go deeper into learning and addressing accessibility best practices.
NOTE:
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