I discussed this with Tim at the hackathon. He suggested that I look at how LocalisationCache has multiple ways to merge the different types of arrays. Similarly ExtensionProcessor / ExtensionRegistry should support the config setting adding some metadata on how these settings should be merged. https://gerrit.wikimedia.org/r/214306 might be a prerequisite to doing that.

Hi I will test this with Confirmaccount using the patch that converts it to extension.json. it may not work because sometimes I may do it wrong or it may work. would need at least one other person to try it to say it works.

I get this error
Fatal error: Call-time pass-by-reference has been removed in /home/simplera/public_html/en/includes/registration/ExtensionRegistry.php on line 127

Shows from error log on the patch this error

08:05:56 127 | ERROR | Call-time pass-by-reference calls are prohibited
08:05:56 | | (Generic.Functions.CallTimePassByReference.NotAllowed)
08:05:56 130 | ERROR | Call-time pass-by-reference calls are prohibited
08:05:56 | | (Generic.Functions.CallTimePassByReference.NotAllowed)

https://integration.wikimedia.org/ci/job/mediawiki-core-phpcs-HEAD/16440/console

Seems that changing setting for extension/skin in localsetting is not working or isent overriding the default setting. this needs to be fixed since that would be classed as extension registration is broken. since no configuration will override it.

And setting for example

$wgConfirmAccountRequestFormItems['Biography']['minWords'] = false;

in localsetting doesent work if you use extension.json for that extension. it just disables the whole bit. It should actually just disable the limit not disable it.

In T99257#1337836, @Paladox wrote:

Setting as unbreak since it doesent work and needs fixing.

This is not unbreak now because it didn't break. It never worked. Nothing in this description that previously worked is now broken. You're trying to use something that doesn't exist yet. The old approach works fine, just keep that for now if JSON isn't working for you.

Well if it was never broken and never implanted then this could be a feature report to suggest that be added to extension registration.

Workarround is to do something like

1. Which form elements to show at Special:RequestAccount

		$features = array(
			# Let users make names other than their "real name"
			'UserName'        => array( 'enabled' => true ),
			# Real name of user
			'RealName'        => array( 'enabled' => true ),
			# Biographical info
			'Biography'       => array( 'enabled' => true, 'minWords' => 50 ),
			# Interest checkboxes (defined in MediaWiki:requestaccount-areas)
			'AreasOfInterest' => array( 'enabled' => true ),
			# CV/resume attachment option
			'CV'              => array( 'enabled' => true ),
			# Additional non-public info for reviewer
			'Notes'           => array( 'enabled' => true ),
			# Option to place web URLs that establish the user
			'Links'           => array( 'enabled' => true ),
			# Terms of Service checkbox
			'TermsOfService'  => array( 'enabled' => true ),
		);

		// Eww, do a 2d array merge so we don't wipe out settings
		global $wgConfirmAccountRequestFormItems;
		if ( $wgConfirmAccountRequestFormItems ) {
			foreach ( $features as $name => $settings ) {
				if ( isset( $wgConfirmAccountRequestFormItems[$name] ) ) {
					$wgConfirmAccountRequestFormItems[$name] += $settings;
				} else {
					$wgConfirmAccountRequestFormItems[$name] = $settings;
				}
			}
		} else {
			$wgConfirmAccountRequestFormItems = $features;
		}

WikiEditor has to do that too. And CollapsibleVector

Ok should wikieditor be updated to do this.

In T99257#1534244, @Paladox wrote:

Ok should wikieditor be updated to do this.

Yep, https://gerrit.wikimedia.org/r/#/c/240961/

Thanks. I've opened a bug about converting extensions that do this.