Your Deepin v20.9 browser is likely being blocked by Cloudflare due to an outdated user-agent, perceived security vulnerabilities, or failed browser integrity checks, all common issues with older or less common browser versions. While other browsers on different OS versions work, upgrading to Deepin v25 (once stable) is the best long-term fix, as its browser has been updated to address these compatibility issues. In the meantime, use an alternative browser like Firefox or Chrome within Deepin v20.9 for Cloudflare-protected sites.