lowflyer

Pocket was already an external product (readitlater?). Send solves a real problem people have, and it was probably easy to develop it separately. Similarly to Monitor, you don't have to touch the core product to make it. Lockwise was probably easy to make, if you already have Firefox Sync, it's just a viewer app.

XUL was used all over the place, so it takes a while to fully remove it. Thunderbird updates the underlying platform only once per year, catching up with Firefox changes in the yearly major release, while Firefox does so every few weeks.

A corp has more flexibility in what it's allowed to do, compared to a US nonprofit. Maybe similar reasons why Mozilla has the Mozilla Corporation in addition to the nonprofit Mozilla Foundation.

To keep money streams and decision making for Firefox and Thunderbird separate?

Based on this Twitter discussion, it seems necessary to update the donation. Possibly because the recipient is no longer a nonprofit (previously Mozilla Foundation), but now a corp (MZLA). https://twitter.com/mozthunderbird/status/122222824579547545...