Please, how does "Subscribe to this forum" function work? I thought I would be notified by e-mail when there is a new topic in the forum I've been subscribed to. Is it correct? I've been subscribed to a few, but I've never been notified about new topics. Thank you.

Hello,
unfortunately, this no longer works, but the info here was never updated. Since about a year, you no longer get emails for topics/forums you are subscribed to.
Instead, now they will appear in a section of the forum called subscriptions, and you can follow them from there.
This was done to prevent the Playroom's e-mail being marked as spam by various providers due to a large number of messages sent.

Emails still work only for your private messages.

PS: I wonder if perhaps, in the future we could get client notifications for subscribed topics at least...