diff --git a/src/Twig/Runtime/IconRuntime.php b/src/Twig/Runtime/IconRuntime.php
index 28430c5..47e6da6 100644
--- a/src/Twig/Runtime/IconRuntime.php
+++ b/src/Twig/Runtime/IconRuntime.php
@@ -84,12 +84,13 @@ final class IconRuntime implements RuntimeExtensionInterface
     private function getSanitisedIconSvg(string $iconName): string
     {
         $iconFilepath = $this->findSvgFilepath($iconName);
-        $rawSvgMarkup = $this->getSvgMarkup($iconFilepath);
-        $cleanSvgMarkup = $this->removeExistingTitleElement($rawSvgMarkup);
-        $cleanSvgMarkup = $this->removeBlackStrokeAttributes($cleanSvgMarkup);
-        $cleanSvgMarkup = $this->removeStrokeCurrentColor($cleanSvgMarkup);
+        $svg = $this->getSvgMarkup($iconFilepath);
 
-        return $this->removeBlackFillAttributes($cleanSvgMarkup);
+        $this->removeExistingTitleElement($svg);
+        $this->removeBlackStrokeAttributes($svg);
+        $this->removeStrokeCurrentColor($svg);
+
+        return $this->removeBlackFillAttributes($svg);
     }
 
     private function findSvgFilepath(string $iconName): string
@@ -110,19 +111,19 @@ final class IconRuntime implements RuntimeExtensionInterface
         return file_get_contents($filepath);
     }
 
-    private function removeExistingTitleElement(string $svg): string
+    private function removeExistingTitleElement(string &$svg): void
     {
-        return preg_replace('/<title>.*<\/title>/', '', $svg);
+        $svg = preg_replace('/<title>.*<\/title>/', '', $svg);
     }
 
-    private function removeBlackStrokeAttributes(string $content): string
+    private function removeBlackStrokeAttributes(string &$svg): void
     {
-        return preg_replace('/stroke(=|:)"?\s*(#0{6}|#000|rgb\(\s*0,\s*0,\s*0\s*\)|black)\s*"?/', '', $content);
+        $svg = preg_replace('/stroke(=|:)"?\s*(#0{6}|#000|rgb\(\s*0,\s*0,\s*0\s*\)|black)\s*"?/', '', $svg);
     }
 
-    private function removeStrokeCurrentColor(string $content): string
+    private function removeStrokeCurrentColor(string &$svg): void
     {
-        return \preg_replace('/stroke=(\'|")currentColor(\'|")/', '', $content);
+        $svg = \preg_replace('/stroke=(\'|")currentColor(\'|")/', '', $svg);
     }
 
     private function removeBlackFillAttributes(string $content): string