Hello. I am wondering how to enable Digital Rights Management In Avast Browser so that I can stream video content.
Hello,
DRM is normally enabled by default
if not, please check that protected content is authorized, and follow the procedure in my screenshots (in French, but you should find your way around).
ps: what operating system are you using?
Because you should know that since about 1 month on older systems (e.g. W7, W8) Google no longer authorizes decryption of protected content in chrome and chrome base browsers (e.g. avast secure browser). 
If you’re not using at least W10, you’ll need to use another browser such as Firefox ESR to continue reading this type of content.
Hi.
Thank you for your prompt and comprehensive reply. I appreciate the time you have given to providing this answer. I am using Win7 so have switched to the latest Firefox ESR and am now able to happily stream CH4 and U.
Kind regards Paul