> Even though Squire isn't meant as a drop-in replacement for web page editing, it still suffers from the same endemic issue that plagues all editors: browser inconsistency.

Squire's purpose is to make things look on-screen and in email the way the user expects it to look. The actual HTML generated is secondary to that. While its nice if it can produce the same HTML every time on every browser, its not especially important.

In terms of UI consistency, its intention is to provide a simple, pleasant editing environment that the user is mostly familiar with it (keyboard controls etc). Again, it doesn't have to be identical everywhere, as long as it does what the user expects.

(Note: I'm a FastMail employee, but not directly involved with Squire).