Cross-posting Markdown doesn't work

[me-and]

I've just tried to cross-post from Dreamwidth to LiveJournal, where the original Dreamwidth post had !markdown in the first line and was correctly formatted as such. The LiveJournal post was cross-posted successfully, but with the raw formatting still in place (* around words that should be italics, double <br> around paragraphs, !markdown on the first line).

I'm using the beta Create Entries page, in case that makes any difference.

[me-and]

@kaberett tells me they're sure they've seen this discussed, but neither of us can find any kind of issue for it…

[kaberett]

HA. Bugzilla 4527.

Relevant info:

If you declare !markdown for a post, the crossposted version has the bare
markdown (including "!markdown"), not interpolated markup.

If we can convert Markdown to HTML for the remote site that would be most
awesome, but if we only strip the markdown from the text that would also be
acceptable!

[...]

zorkian@2a9e8c7

Temporary patch, this doesn't work entirely as it doesn't support
opt_preformatted which we have to set on the remote post.

If someone has the time/inclination, please grab this bug.

[kareila]

@zorkian did some initial work on this which is still viewable here: zorkian@2a9e8c7

The given caveat is that it doesn't send opt_preformatted to the remote site, plus @alierak pointed out significant overlap with existing code in LJ::CleanHTML::clean_event.

[kareila]

claiming