As far as I know: not.
[quote="Nit, post:6, topic:11531"]
Note (to myself) that this can be fix then support for Must-Staple / TLS-Feature will be deployed to the production boulder (An letsencrypt client option could also be added to ease deployment of this cert extension).[/quote]
Unfortunately, browser support for Must-Staple is quite premature.. Firefox has the feature in the development version (45), but that version isn't stable yet.. Chrome doesn't have support at all. I don't know about other browsers.