robchur wrote:

It's possible. The question is, "are we going to?"

Unregistered users can still manually revert changes, etc. This just makes it a
little easier to do.

michael.frey wrote:

You can also give unregistered users the revert button, because they can manully
revert ...

I think, it isn't logic that an unregisterd user doesn't have a revert button,
but they have the undo button.

And other thing of undo is, that we can't see the usage.
When a admin use the revert button, it's documented as summary.

robchur wrote:

Undo doesn't do an immediate save, though, so it's not in the same league as
rollback.

rotemliss wrote:

If a user wants to manually revert an edit, he has to do the following:

1. View the diff.
2. Click "edit" for the old edit.
3. Save.

If a user wants to undo an edit, he has to do the following:

1. View the diff.
2. Click "undo" for the new edit.
3. Save.

It's almost the same, and since the first one is available for every user, the
second one can also be available for every user.

However, if a *sysop* wants to revert an edit, he has to do the following:

1. View the diff.
2. Click "revert".

which is much more intuitive and quick, and therefore is only available for
sysops. "Undo" is not like that, and therefore it can be available for every user.

About the undo edit summary:

1. Manual revert also does not have an automatic summary.
2. Automatic summary for undo was added (though it can be deleted by the user, I

think), and will be soon available on Wikimedia sites.

I think that this is a solution in search of a problem. If it appears that
vandals are using undo to vandalise, then we might consider limiting it. At the
moment, however, I see no reason to disable this for unregistered users.

One problem with unregistered users capable to use the "undo" feature, would be
users on a shared connection (like AOL), as an vandal could then undo all the
edits made by those on that ip during that moment.

(In reply to comment #6)

One problem with unregistered users capable to use the "undo" feature, would be
users on a shared connection (like AOL), as an vandal could then undo all the
edits made by those on that ip during that moment.

I don't understand. You seem to be under the impression that (undo) is a kind of
self-rollback. It's not - it's the ability to undo a specific not on-top edit
(see bug 6925).

Excuse-me, I insist and reopen the bug. I'm sysop on frwiki and I aggree with Michael Frey.
I agree the "revert" can be reproduce artificially with numbers of clicks.
But the new "undo" link in the history reduces the number of clicks to 2, so the speed of the vandal increase of 1/3.
I find also a anon should not have the two "edit" link in a diff, but it's not the subject.

To resume I dislike the facility given to the anon to revert, it gives more power to vandals (even if some anon can use it to revert a vandal).
In frwiki we are several users to find the "undo" in the history bad for vandalism. But useful for other users.

robchur wrote:

That's nice, dear.

Thank for your (very very) quick reply, but I doubt you have read me entirely, that's just too bad.

So now we must fight vandalism with this wonderful feature.
Somebody has propose to hide this via CSS (for everybody), perhaps we will make that if there is too vandalism by this way.

I was just wondering why this is being looked at as a black and white matter. The above discussion makes me think people either think undo should be available to anonymous editors, or they think it should be disabled. I was just wondering a "grey" solution: To find a way (perhaps by creating an extension and installing it in Wikimedia wikis) to let the sysops decide wheather anon users can undo or not.

By the way, on some wikis (I think French Wikipedia is one) pieces of Javascript are added to the common.js file which forces anonymous users to preview their edit befor they can send it. Although this is not a complete solution (people may turn Javascript off or even use user JSs which undo that solution), it can be used as a remedy for the anonymous user vandalisms by undoing pages.

Just my two cents...