https://filmpreservationsociety.org/biograph-project
They post on Facebook and Twitter; I don't participate on those platforms. I know about the project from a friend who's close to Tracey Goessel, the author of the Fairbanks biography. She loves her Doug.
The Three Musketeers will be released by the good and very reliable people in charge of the Biograph Project. It'll probably see the light of day in 2022. It's a full restoration, and I'm looking forward to it.