diff --git a/src/View/Requirements_Backend.php b/src/View/Requirements_Backend.php
index d0bde0851..1316ae123 100644
--- a/src/View/Requirements_Backend.php
+++ b/src/View/Requirements_Backend.php
@@ -65,7 +65,7 @@ class Requirements_Backend
      * @config
      * @var bool
      */
-    private static $resolve_relative_css_refs = true;
+    private static $resolve_relative_css_refs = false;
 
     /**
      * Paths to all required JavaScript files relative to docroot
@@ -1456,11 +1456,11 @@ MESSAGE
         $fileUrl = Injector::inst()->get(ResourceURLGenerator::class)->urlForResource($filePath);
         $fileUrlDir = dirname($fileUrl);
         $content = preg_replace_callback('#(url\([\n\r\s\'"]*)([^\s\)\?\'"]+)#i', function ($match) use ($fileUrlDir) {
-            [ $_, $prefix, $relativePath ] = $match;
+            [ $fullMatch, $prefix, $relativePath ] = $match;
             if ($relativePath[0] === '/' || false !== strpos($relativePath, '://')) {
                 return $prefix . $relativePath;
             }
-            $full = FilesystemPath::canonicalize($fileUrlDir . '/' . $relativePath);
+            $full = FilesystemPath::canonicalize(FilesystemPath::join($fileUrlDir, $relativePath));
             return $prefix . $full;
         }, $content);
         return $content;
diff --git a/tests/php/View/RequirementsTest.php b/tests/php/View/RequirementsTest.php
index 727d26eb0..69144ea5b 100644
--- a/tests/php/View/RequirementsTest.php
+++ b/tests/php/View/RequirementsTest.php
@@ -280,7 +280,7 @@ class RequirementsTest extends SapphireTest
         $this->assertStringContainsString(
             ".p4 { background: url(/four.gif); }",
             $content,
-            'combined css url resolver decoded 4 double-dot when only 4 levels available'
+            'combined css url resolver decoded 4 double-dot when only 3 levels available'
         );
 
         /* COMBINED CSS URL RESOLVER MODIFIED AN ARBITRARY VALUE */