Some Hex users experienced issues with HTML not rendering properly in notebooks and apps due to compatibility problems with certain VPN and web firewall providers. The root cause was identified as an upstream issue with these third-party providers rather than Hex's platform directly. Hex worked with the affected VPN and firewall providers to resolve the compatibility issues, with most users seeing resolution after restarting their browsers, though the full fix took approximately 20 days to complete across all provider configurations.