diff --git a/LocalSettings.php b/LocalSettings.php
index fe4cd08..406442d 100644
--- a/LocalSettings.php
+++ b/LocalSettings.php
@@ -79,7 +79,7 @@ $wgMemCachedServers = [];
 ## To enable image uploads, make sure the 'images' directory
 ## is writable, then set this to true:
 $wgEnableUploads = true;
-$wgFileExtensions = array_merge( $wgFileExtensions, array( 'pdf', 'svg' ));
+$wgFileExtensions = array_merge( $wgFileExtensions, array( 'pdf', 'svg', 'stl' ));
 $wgUseImageMagick = true;
 $wgImageMagickConvertCommand = "/usr/bin/convert";
 $wgGenerateThumbnailOnParse = true;