Consider adding support for Mongolian text layout.

[siqinbilige]

Mongolian-based systems are typically written using a top-to-bottom inline direction with a rightward (left-to-right) block flow direction. There is no Monglian text editor on Mac and iOS. Mongolian text layout is same as the vertical layout which CotEditor has. Except the lines line up from left to right. https://www.w3.org/TR/css-writing-modes-3/#text-flow

[1024jp]

It's actually way harder than the current CotEditor's vertical layout, because Apple doesn't provide any API for vertical+left-to-right text layout.

However, I'm personally interested in implimenting this feature. I can't say "I'll do it" now, but I'll consider.

[1024jp]

cf. How do you make a vertical text UILabel and UITextView for iOS in Swift? -Stack Overflow