Really? Updated Firefox v135 web browser is not supported to watch videos (e.g., https://therokuchannel.roku.com/details/a63a196f095a5aa2a26c8a12dba4319f) on Roku.com's web site on my 64-bit W10 Pro. PC? Also, its "Try these supported browser(s) instead." goes to https://support.roku.com/article/360007223934 which is about "How to get The Roku Channel..." I see nothing about web browsers.
Thank you for reading and hopefully answering.
Firefox normally has DRM (digital rights management) disabled by default.
Try going into Firefox Settings, then Search in settings for DRM. (check box to Enable)
Otherwise, DRM should be under Settings/General in Firefox.
Then clear the Firefox cache/history, close Firefox Browser, and then Restart/Launch Firefox browser again.
Firefox normally has DRM (digital rights management) disabled by default.
Try going into Firefox Settings, then Search in settings for DRM. (check box to Enable)
Otherwise, DRM should be under Settings/General in Firefox.
Then clear the Firefox cache/history, close Firefox Browser, and then Restart/Launch Firefox browser again.
"Digital Rights Management (DRM) Content -- Play DRM-controlled content..." was already enabled. Weird, now the video works. Maybe my Firefox restart fixed it.