[HarfBuzz] Tai Tham Ligature u1A31 RANA u1A2C NYA not formed in FFX v. 21

[Jonathan Kew]

On 29/4/13 22:08, Ed Trager wrote:
> Hi, List,
>
> Which version of HarfBuzz-NG is in the latest Firefox v. 21 on the beta
> channel?

I don't recall exactly without some digging, but it'll definitely be at 
least a couple of months old.

> When I run hb-view version 0.9.16 against my Tai Tham font,
> the ligature u1A31 RANA + u1A2C NYA is formed correctly (as shown in the
> first attachment, out5.png).
>
> However, when I render the same combination in Firefox v. 21.0, the
> RANA+NYA ligature is *not* formed ( but, curiously, the u1A36 NA + u1A63
> VOWEL SIGN AA ligature is correctly formed as expected ) (image also
> attached).
>
> So it looks like a rather odd bug in FFX perhaps?

How does it behave in Aurora and/or Nightly builds?