Out of the blue, Square Enix released a big new update to Final Fantasy 3.
The patch was made available overnight to Final Fantasy 3 owners on Steam, as well as Android and iOS. It brings a new UI to the PC version, as well as 21:9 support.
The font in the game's various menus and screens has also been improved (thanks, @FeoUltima), and Square added a bunch of new languages to the Steam version that include Traditional and Simplified Chinese, Japanese, Korean, and Thai.
All versions of Final Fantasy 3 now also benefit from a gallery mode, and new 2x speed in auto battle.