Blimey, that is an omission.

I always liked that Bootstrap 3 was so inclusive of screenreaders, and as a LTR reader, would never have guessed that RTL support wasn't there if you hadn't pointed it out.

Definitely need to do it. We tried to do it as part of v3 but ultimately left it to the community. We saw a few good things come of it, but it's on my bucket list for the future.