[Xiph-Advocacy] current status of embeded subtitle format support?

What is the current status of major player's suport over the 4
subtitle formats of ogg/ogm files?

It's actually quite hard to find out. I spent 1 hour googling already.

First, it is difficult to find sample files with each of these
subtitles to test on the players you already have - in fact, I failed
to find any sample of any embeded subtitles.

And then the description isn't clear if you look at player's feature
list. e.g. Gnome's Totem project page has a feature list, which says
it supports ogg/ogm embeded subtitle, but didn't specify which - you
would assume the most popular one, but Kate is the most popular (by
google trends) and its support is still on Totem's bug tracker, open.

If someone can point me to a source, or just write them here, I'll do
the simple work of properly place it on related wikipedia pages so the
next advocator knows where to look.

Best.