Comment by BrendanEich

A mundane reason for why donations to the 501c3 parent Mozilla Foundation can't go to Firefox or Gecko engineers is U.S. tax law. We found out the hard way after the IRS San Jose office said we could run only as a foundation and take "sponsorship income" tax-free. They reneged and litigated; this led to the creation of the arms-length Mozilla Corporation that's wholly owned by the Foundation. Per IRS regulations, it cannot be funded by grants from the parent Mozilla Foundation.

The corporation could let users pay for Firefox, and pay tax on that revenue. While I was there, no one thought this would help enough to be worth the effort, compared to just working on other things while taking Google search revshare.

With Brave, I've pushed for user-pays as an option. We let a user buy Premium Search (no ads, but this is possible for free) to support us. It's a small but non-negligible amount of revenue per year, and growing slowly, but we did it on principle. Same will go for buy-once zero-telemetry Brave Origin, stripped down Brave coming in a month or two.