I guess this is possible, but can you help me:
Hello, just click on "Convert to message" link on the comment and select helpdesk forum. After that you can continue private discussion with him.
Thank you for the answer: didn't know that (after converting to topic) this could become private.
And also another related question:
And then (if above private discussion with multiple users is possible)
My idea is indeed to solve this kind of situation:
I'd like to:
Thank you for the answer: didn't know that (after converting to topic) this could become private.then, how to switch to private afterwards?
When you click "Convert to topic" you have to select a forum where this topic will be. If you choose a helpdesk the topic will be converted into ticket and become private.
is a private discussion limited to ONE user (and the admins)? or it is possible to have a private discussion with a few users?
You can add collaborators to tickets. Just click three dots button and select "Manage collaborators"
is there a solution to merge some following comments into the created private topic? (to group the comments that follows the first one converted into private topic)
Unfortunately, no. You can create few topics from comments then merge them. But probably easier just create one and add collaborators to the topic.