Discussion notification opt-in and opt-out

[rwi]

After participating in a discussion by starting it or adding a comment, you will be sent notifications for every new reply added, even if you are not mentioned in that note. This is useful in some situations but could also be annoying in others. Currently, you only have the possibility to disable this feature completely. This should be more flexible so that you can opt-out from notifications for any discussion you participated in.

On the other side you might spot a discussion you haven't contributed to yet but think that it is interesting and would like to get notifications for new replies. Moreover, if you used the option to completely deactivate notifications for discussions you took part in, it would be nice to have a way to be notified about activities in certain discussions. Therefore, there should be a feature to activate notifications on selected discussions.

Feature details:

• A new option is added to the notification settings in the user profile configuration which activates a feature that allows receiving notifications for discussion you didn't participate in.
• If this option is activated, a new action named 'Watch' is added to the More menu of the root note of a discussion you didn't participate in.
• After clicking this action you will be sent notifications (email or jabber) when new comments are added, even if you are not mentioned.
• When clicking the action a 2nd time the notifications are disabled again.
  • The action link could behave similarly to 'like', that is it is crossed-out on hover if notifications are currently enabled.
• The action will also be shown for the root of a discussion you participated in. Depending on the state of the existing setting for enabling the discussion notifications a click will lead to deactivating (setting enabled) or activating the notifications.
• If both settings are disabled the action isn't shown.