Hello, guys.
Fix spoiler on quick post/edit is quite trivial. Main what we must doing it is attach event handler not only to page ready, but to post add/change too.
Please see attached patches.
One additional note. In archive bundled 2 patches, first, called "
quick-post|edit.old.patch" is "quick" fix. But I also suggest (really this idea was by Plague admin of imho.ws

) move function initSpoilers and its attachment to document ready event into external file to allow caching it by browser. And full changes present in "
quick-post|edit.patch".
With best wishes, Pavel.