This feature was introduced in rP568b0e06e7d54618c2afade1cf409912bf90add9.

Personally speaking, this prefix only makes spotting the page title in a browser tab harder when having numerous tabs opened.

Plus my workflows don't rely on web notifications.

Plus every single opened Phorge page shows that number in the top bar anyway. Is it so important to see it also when having another browser tab opened?
I understand that "sense of urgency" which other social media platforms want to imply via this feature so you keep engaged and stay on their platform and have to see more advertisements.
But I don't get that for Phorge, especially as in our downstream instance we uninstalled Conpherence.
And upstream Phorge already seems to change its favicon anyway in case of new Conpherence messages, so why duplicate things in that case?:

YMMV, of course.

(PS: I only ended up looking into this as I received complaints that opening the Notifications dropdown in the top bar and selecting Mark All Read reloads the entire web page but of course does not reload any other Phorge pages being opened in the web browser, thus still showing that unread count prefix.)