(a) should be done through your preferences. Go to the tab "Watchlist" and check the 4 boxes at the bottom (watch pages I create/edit/move/delete).
(b) if you have to watch more than a handful or pages related to a problem user, just block him. I do not see a reason to add this, as the use case is extremely specialised, and the links would appear in the contributions links for everyone, cluttering the UI.

WONTFIX, if I would decide.

robert wrote:

Adds a watch link beside every entry within Special:Contributions when logged in

Adds a watch or unwatch link beside every entry within Special:Contributions when logged in. Possible issues:

• Takes user away from the page, it is easy to return (via the back button) and so isn't significant - an AJAX solution would be nice though (perhaps as a follow up bug though).
• Uses strtolower on the translation which may or may not be an issue, since although it is a one word this could still be problematic dependant on language. Another message should be added for this if this does turn out to be bad.
• Once the user is taken to the watch\unwatch confirmation page the return link is to the page they have watched, rather than Special:Contributions - tried using returnto= but this does not work.

Attached:

robert wrote:

Consensus is to close as WONTFIX as it is clutter (could be implemented as a gadget if desired, and probably done more effectively that way).

ayg wrote:

Agree with WONTFIX, this seems cluttery. I don't find the use-case compelling enough to add another button here. In fact, it doesn't really make sense. If it's a problem user, you should be looking at their diffs, not at *subsequent* edits by *other people* to the page they just edited. And as for you, well, you can watch all pages you edit by default. That should be enough.