Here in my Firefox window I have some highlighted text. In my head this is, perhaps, the X Primary selection. For a transient period in time it is also X Cut Buffer 0. From Firefox's context menu I've selected Copy, so it should now also be in the X Clipboard selection. However, in the Emacs buffer I wanted to paste to, it is not in any of these places. I don't know where it is. Why is this, exactly? I've read what is probably the clearest doc available on what should be happening (Note that despite the fact that Emacs has scragged the X Primary selection through a kill operation in another window, the text remains highlighted in Firefox). Someone here is not reading from the correct hymn sheet, and I want them found and shot, because if I select and copy text I fully expect it to be available to the next application that says, "insert clipboard contents here". Of course, it could well be that emacs, in its wisdom, is scragging the X Primary selection, X Cut Buffer 0, and the Clipboard all in one go... gah.

Much as I am in favour of doing everything in Emacs, this is demented.

Turns out that the Emacs lj Client simply doesn't know any security modes except public and private, and if you don't specify private it assumes public. Bad client! No cookie!