Angela Beesley's wiki

Useful though it is, I don't like the preventing access page in the MediaWiki manual since it has no opposite. There is no "allowing access" page. There is no suggestion that some wikis might actually benefit from giving more people access to the tools rather than fewer.

On this wiki, everyone can rollback bad edits.

Making it easy for everyone to revert bad edits is one way of dealing with vandalism.

It's simple to allow this, just add one line to your LocalSettings.php:

$wgGroupPermissions['*']['rollback'] = true;

Now, there is a downside to allowing everyone to do this. If you visit a user's contributions list, you could quickly revert every edit they'd ever made (it's not a one step process, but it's quick). If that user was not a vandal, that would be annoying and you want to avoid making things easier for the vandals than the people reverting them.

The best way to deal with this is to allow the [rollback] option to everyone but only on page diffs, and not on user contributions lists. This makes it very quick to revert one bad edit but not especially quick to rollback lots of bad edits (no quicker than common vandalism anyway).

You should leave the feature in place for admins (people with the "delete" permission) by making these changes to SpecialContributions.php:

Edit SpecialContributions.php and replace

if ( $wgUser->isAllowed( 'rollback' ) && $wgRequest->getBool( 'bot' ) ) {

with

if ( $wgUser->isAllowed( 'delete' ) && $wgRequest->getBool( 'bot' ) ) {

and

if( $wgUser->isAllowed( 'rollback' ) ) {

with

if( $wgUser->isAllowed( 'delete' ) ) {

Why "delete"? Because if someone is trusted to delete pages, they should also be trusted to revert all contributions of a user easily. If you prefer, you could add a new user group and use the name of that instead.