Response below/inline for email gfp wrote:
> (original email sent 25 Dec 2024 at 09:22)
> 
> When I opening Thunderbird, and I am connected to the internet,
> I see all my folders (if I also scroll down, because I have many)
> and see immediately all new incoming emails in the specific folders,
> I have created, because the folders with the new emails
> turn in bold letters.

[...]

> Is that also achievable in GNUS?
> with groups?

Yes, the "Group" buffer will show all groups (folders in your speak)
that have unread messages (with the number of unread indicated) or it
can be configure so that it shows all groups with or without unread
messages.

Attached is a little screenshot of part of the view of my Groups buffer.
The *in the emacs help line is indicating that I am currently visiting
that group (and actually responding to a post there, i.e. this post that
I am writing at the moment).

-- 
Eric S Fraga via gnus (Emacs 31.0.50 2024-12-17) on Debian 12.8