The Theora video compression codec is finally being put out to pasture as Google pulls it from Chrome and Mozilla mulls the same for Firefox.

It's been a while coming. Theora first showed up nearly 20 years ago, but more than a decade has passed since any serious development was done. In light of an increasingly chalenging security environment, browser makers are always considering where the next hole might be lurking.

It was only in September that Google and Mozilla had to rush out fixes for a webp vulnerability. With few updates over the years, Theora's codebase could pose various risks from potential malware exploits.

According to the Chrome platform development team: "A spike in zero day attacks against media formats has caused us to reevaluate our support for legacy codecs."

The other factor is the codec's low usage. Google noted it had fallen below measurable levels, certainly when compared to more modern codecs, such as VP9. Support for the Ogg container format, also maintained by the Xiph.org foundation, is not being removed.

The deprecation and removal will be a gradual process, during which time the codec can be reactivated via a Chrome flag if needed. 50/50 experiments in the canary branch began in October and were planned to move to the beta branch in November. In December, the change will trickle into the stable branch before the code and flag are finally removed in February 2024 and rolled out with Chrome 123 in March 2024.

Neither Safari nor Chrome on Android have ever supported the codec, and Mozilla seems to be considering a similar stance to Google, noting that the codec accounted for approximately 0.09 per cent of media resource loads, and services that made use of Theora content (Wikipedia was given as an example) had moved on.

Mozilla plans to disable Theora support in Firefox Nightly. Some telemetry will be added to provide developers with insights on the impact - such as instances when a media load fails due to loss of support. If all goes well, Mozilla will follow Chromium's timeline and deprecate Theora early next year. ®

https://www.theregister.com//2023/11/02/theora_video_codec_deprecation/