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

example:

How it works:

• By clicking the script's PM icon, the script always gets you to a "Create a new conversation" page (https://greasyfork.org/en/users/your_username/conversations/new?other_user=target_username).
• In contrast, by clicking the the site's built-in"Send message" link:
  • if you haven't sent any PM before,
    it gets you to a "Create a new conversation (https://greasyfork.org/en/users/your_username/conversations/new?other_user=target_username)
  • if you have send PMs before,
    it gets you to a "Conversation with user" page (https://greasyfork.org/en/users/your_username/conversations/___)
    where all your previous PMs are displayed in the same page,
    and you have to scroll down to reach the "Post Reply" form.

Notes:

• the button doesn't appear in your own Greasyfork profile page, and it only works when you are logged in, for obvious reasons,
• it is compatible with Citrus GFork.

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