Facebook is under a lot of scrutiny and pressure at the moment. It's accused of helping foreign actors to subvert elections by using ads and fake accounts to spread lies—in the US, for example—and of acting as a conduit for terrorism in New Zealand and elsewhere. There are calls to break up the company or at least to rein it in.
In an evident attempt to head off those moves, and to limit the damage that recent events have caused to Facebook's reputation, Mark Zuckerberg has been publishing some long, philosophical posts that attempt to address some of the main criticisms. In his most recent one, he calls for new regulation of the online world in four areas: harmful content, election integrity, privacy and data portability. The call for data portability mentions Facebook's support for the Data Transfer Project. That's clearly an attempt to counter accusations that Facebook is monopolistic and closed, and to burnish Facebook's reputation for supporting openness. Facebook does indeed use and support a large number of open-source programs, so to that extent, it's a fair claim.
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From same author today: Facebook Fails To Block EU Court Case That Could Rule Against Most Transatlantic Data Flows [3]