Currently using a colon in a meta directive name produces an error. Twitter Cards and Open Graph use colons in their names. An example for Twitter Cards could look like this:
.. meta::
:twitter:card: summary
:twitter:site: @nytimesbits
:twitter:creator: @nickbilton
Unfortunately this raises an "Invalid meta directive." error. Is there a possibility to escape the colons? Adding a backslash in front of the middle colon raises no error but the backslash is not removed when rendering the HTML and ends up in the document.
Fixed in r8169. You can use a backslash to escape the colons. But here the embedded colons are unambiguous so I enabled their use without backslash-escapes as well.
Sorry for the long delay. This was recently brought to my attention. Thanks for the bug report!