https://medium.com/@slsoftworks/why-should-one-keep-an-eye-out-for-servo-6d53eb6f64ff
Servo is currently basically the only browser engine that supports native rendering of vertical texts
As much as I love hearing from people that Servo is awesome, this is not correct.
First, vertical text support in Servo is currently (2014-12-01) experimental (behind an off-by-default flag), in early stages of development, and very buggy. So saying that we support is is a bit of a stretch :)
Second, other browsers have it too, although I don’t know how complete or how buggy. Microsoft has had some form of it since IE 5 (!), WebKit/Blink have it prefixed, and Firefox has it in Nightly.