Since the latest forum update a new plugin is enabled by default which lets you see who is currently writing a reply to the topic you are looking at (at the bottom of the thread).
The goal of that plugin is probably to avoid two people giving the same answer to a question.
But the downside is that some people may not answer at all if they see someone else already does even though they may have a unique point of view to offer.
Also personally it just makes me nervous when I see someone starting to write a reply when I’m just writing mine.
So what I go is simply use uBlock Origin to hide the elements of that plugin.
Here is the element you have to block:
If more people dislike this plugin than think it’s helpful we can also disable it for everybody.
PS: The full entry in uBlock’s “My filters” panel has to look something like this:
! 2/8/2018, 10:05:15 PM https://forum.fairphone.com/* forum.fairphone.com##.presence-users
The date is of course not important. What’s important is that you block the element on all of forum.fairphone.com. If you simply use the element picker mode within a topic to block the element you’ll only block it in that topic.