diff --git a/extension.json b/extension.json
index 8289d0ea4..61ec7af36 100644
--- a/extension.json
+++ b/extension.json
@@ -91,11 +91,10 @@
 		}
 	},
 	"config": {
-		"_prefix": "",
-		"wgCaptchaWhitelistIP": false,
-		"wgCaptcha": null,
-		"wgCaptchaClass": "SimpleCaptcha",
-		"wgCaptchaTriggers": {
+		"CaptchaWhitelistIP": false,
+		"Captcha": null,
+		"CaptchaClass": "SimpleCaptcha",
+		"CaptchaTriggers": {
 			"edit": false,
 			"create": false,
 			"sendemail": false,
@@ -105,18 +104,18 @@
 			"badloginperuser": true,
 			"_merge_strategy": "array_plus"
 		},
-		"wgCaptchaTriggersOnNamespace": {
+		"CaptchaTriggersOnNamespace": {
 			"_merge_strategy": "array_plus_2d"
 		},
-		"wgCaptchaStorageClass": "CaptchaSessionStore",
-		"wgCaptchaSessionExpiration": 1800,
-		"wgCaptchaBadLoginExpiration": 300,
-		"wgCaptchaBadLoginPerUserExpiration": 600,
-		"ceAllowConfirmedEmail": false,
-		"wgCaptchaBadLoginAttempts": 3,
-		"wgCaptchaBadLoginPerUserAttempts": 20,
-		"wgCaptchaWhitelist": false,
-		"wgCaptchaRegexes": []
+		"CaptchaStorageClass": "CaptchaSessionStore",
+		"CaptchaSessionExpiration": 1800,
+		"CaptchaBadLoginExpiration": 300,
+		"CaptchaBadLoginPerUserExpiration": 600,
+		"AllowConfirmedEmail": false,
+		"CaptchaBadLoginAttempts": 3,
+		"CaptchaBadLoginPerUserAttempts": 20,
+		"CaptchaWhitelist": false,
+		"CaptchaRegexes": []
 	},
 	"manifest_version": 1
 }
diff --git a/includes/ConfirmEditHooks.php b/includes/ConfirmEditHooks.php
index 71ffee94f..a77638b5a 100644
--- a/includes/ConfirmEditHooks.php
+++ b/includes/ConfirmEditHooks.php
@@ -87,12 +87,24 @@ class ConfirmEditHooks {
 	 * Set up $wgWhitelistRead
 	 */
 	public static function confirmEditSetup() {
-		global $wgCaptchaTriggers, $wgWikimediaJenkinsCI;
+		// @codingStandardsIgnoreStart MediaWiki.NamingConventions.ValidGlobalName.wgPrefix
+		global $wgCaptchaTriggers, $wgWikimediaJenkinsCI, $ceAllowConfirmedEmail,
+		       $wgAllowConfirmedEmail;
+		// @codingStandardsIgnoreEnd
 
 		// There is no need to run (core) tests with enabled ConfirmEdit - bug T44145
 		if ( isset( $wgWikimediaJenkinsCI ) && $wgWikimediaJenkinsCI === true ) {
 			$wgCaptchaTriggers = array_fill_keys( array_keys( $wgCaptchaTriggers ), false );
 		}
+
+		// $ceAllowConfirmedEmail is deprecated and should be replaced by $wgAllowConfirmedEmail.
+		// For backward-compatibility, keep the value for some time. T162641
+		if ( isset( $ceAllowConfirmedEmail ) ) {
+			wfDeprecated(
+				'Using $ceAllowConfirmedEmail is deprecated, ' .
+				'please migrate to $wgAllowConfirmedEmail as a replacement.' );
+			$wgAllowConfirmedEmail = $ceAllowConfirmedEmail;
+		}
 	}
 
 	/**