https://connect.mozilla.org/t5/discussions/request-hevc-h-265-drm-support-on-windows-firefox/m-p/106471#M41125 <P>Dear Firefox Team,</P><P>Currently, Firefox on Windows cannot play HEVC (H.265) DRM 4K streams, even with the Microsoft HEVC codec installed. This works fine on Linux and in Chrome/Edge on Windows.</P><P><STRONG>Key technical context:</STRONG></P><UL><LI><P>Firefox on Windows relies on Windows Media Foundation + Widevine for DRM.</P></LI><LI><P>WMF does not expose HEVC for DRM streams, so playback fails.</P></LI><LI><P>Non-DRM HEVC files play fine, showing the codec itself is functional.</P></LI></UL><P>Adding HEVC + DRM support on Windows would let users enjoy 4K content in Firefox without switching browsers, improving the experience and keeping Firefox competitive.</P><P>Thank you for considering this feature!</P><P>Best regards,</P><P>De_Lo_</P> Sun, 28 Sep 2025 10:04:47 GMT De_Lo_ 2025-09-28T10:04:47Z https://connect.mozilla.org/t5/discussions/request-hevc-h-265-drm-support-on-windows-firefox/m-p/106471#M41125 <P>Dear Firefox Team,</P><P>Currently, Firefox on Windows cannot play HEVC (H.265) DRM 4K streams, even with the Microsoft HEVC codec installed. This works fine on Linux and in Chrome/Edge on Windows.</P><P><STRONG>Key technical context:</STRONG></P><UL><LI><P>Firefox on Windows relies on Windows Media Foundation + Widevine for DRM.</P></LI><LI><P>WMF does not expose HEVC for DRM streams, so playback fails.</P></LI><LI><P>Non-DRM HEVC files play fine, showing the codec itself is functional.</P></LI></UL><P>Adding HEVC + DRM support on Windows would let users enjoy 4K content in Firefox without switching browsers, improving the experience and keeping Firefox competitive.</P><P>Thank you for considering this feature!</P><P>Best regards,</P><P>De_Lo_</P> Sun, 28 Sep 2025 10:04:47 GMT https://connect.mozilla.org/t5/discussions/request-hevc-h-265-drm-support-on-windows-firefox/m-p/106471#M41125 De_Lo_ 2025-09-28T10:04:47Z