By default you may send a pm via a user's forum profile page (e.g. see link 1). With this script you may also send a pm via user's Greasyfork profile page (e.g. see link 2).
Forum profile: https://greasyfork.org/en/forum/profile/1/JasonBarnabe Greasyfork profile: https://greasyfork.org/en/users/1-jasonbarnabe
The script was not working ok (because you have to simulate a keypress sequence -with a delay between each press-
in order the username to be "typed" in the autocomplete popup, and so the script to be able to click it, to select it).
I fixed it, but, in order to manage sending this simulated keypress sequence ( 1-line in the script! - line 47)
I have to use the following
The fact that these
require's are needed in order by the
jquery-simulate-ext plugin to work,
is documented here: https://github.com/j-ulrich/jquery-simulate-ext#usage.
And, I also use arrive.js in the script.