diff --git a/includes/resourceloader/ResourceLoaderStartUpModule.php b/includes/resourceloader/ResourceLoaderStartUpModule.php
index 7b2d532d131..eb9788c0ce9 100644
--- a/includes/resourceloader/ResourceLoaderStartUpModule.php
+++ b/includes/resourceloader/ResourceLoaderStartUpModule.php
@@ -66,6 +66,8 @@ class ResourceLoaderStartUpModule extends ResourceLoaderModule {
 			}
 		}
 
+		$illegalFileChars = $conf->get( 'IllegalFileChars' );
+
 		// Build list of variables
 		$vars = [
 			'wgLoadScript' => wfScript( 'load' ),
@@ -107,6 +109,7 @@ class ResourceLoaderStartUpModule extends ResourceLoaderModule {
 			'wgResourceLoaderMaxQueryLength' => $conf->get( 'ResourceLoaderMaxQueryLength' ),
 			'wgCaseSensitiveNamespaces' => $caseSensitiveNamespaces,
 			'wgLegalTitleChars' => Title::convertByteClassToUnicodeClass( Title::legalChars() ),
+			'wgIllegalFileChars' => Title::convertByteClassToUnicodeClass( $illegalFileChars ),
 			'wgResourceLoaderStorageVersion' => $conf->get( 'ResourceLoaderStorageVersion' ),
 			'wgResourceLoaderStorageEnabled' => $conf->get( 'ResourceLoaderStorageEnabled' ),
 			'wgResourceLoaderLegacyModules' => self::getLegacyModules(),
diff --git a/resources/src/mediawiki/mediawiki.Title.js b/resources/src/mediawiki/mediawiki.Title.js
index ff4d1c20cb9..4c57faa6c82 100644
--- a/resources/src/mediawiki/mediawiki.Title.js
+++ b/resources/src/mediawiki/mediawiki.Title.js
@@ -213,7 +213,7 @@
 		},
 		// slash, colon (not supported by file systems like NTFS/Windows, Mac OS 9 [:], ext4 [/])
 		{
-			pattern: /[:\/#]/g,
+			pattern: new RegExp( '[' + mw.config.get( 'wgIllegalFileChars', '' ) + ']', 'g' ),
 			replace: '-',
 			fileRule: true
 		},