Viewers of a discussion may request writer rights (see Participant Rights and Roles). To request writer rights, click on the three horizontal bars at the top-left of the screen to open the discussion menu and select ‘Request Writer Rights’. You will be asked to provide an (optional) reason for requesting writer rights. If a discussion is private and you do not have Viewer rights to it, you’ll be offered the option of requesting writer rights when you follow a URL to the discussion.
Only discussion Admins and Owners can approve users’ writer rights requests. While writer rights requests are enabled by default, Admins and Owners can choose to turn them off - to do so, click on the three horizontal bars at the top-left of the screen to open the discussion menu and select ‘Discussion Settings’. Deselect ‘Allow participation requests’.