In Bug #4023, Steve suggested:
> > Perhaps there could be a "help" popup saying more about date/time formatting.
> I think that's a good idea. I'll have to give it some thought.
Another way would be to provide a link to a page documenting the format.
AFAICT, there isn't anything as concise as the "date" man page.
Accepting the bug I just created...
There's now a help button in the preferences that takes you to the web page (r4884).
The web page now shows date formats. I'll make it look prettier later.
(In reply to comment #2)
> There's now a help button in the preferences that takes you to the web page
Thanks for adding the help button. It fits perfectly in the properties dialog.
> The web page now shows date formats. I'll make it look prettier later.
And thanks for adding the table of format specifiers.
The mention of "strftime()" could be linked to a web page documenting the function in detail. (I have edited Wikipedia quite a bit, so linking anything remotely in need of explanation is instinctive.)
There is a minor problem that may not be related to the plugin or exo-open, but the browser window opens *behind* the properties dialog and it cannot be brought to the front without closing the dialog. The browser window can be resized and moved, so it is still possible to put the two side-by-side so that the documentation and the custom format box can be seen at the same time.
(I am using Firefox 3.0b5.)