diff --git a/src/Symfony/Component/VarDumper/Dumper/CliDumper.php b/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
index 690f6d016791b..e2b7dad358c3f 100644
--- a/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
+++ b/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
@@ -564,6 +564,10 @@ protected function supportsColors()
      */
     protected function dumpLine(int $depth, bool $endOfValue = false)
     {
+        if (null === $this->colors) {
+            $this->colors = $this->supportsColors();
+        }
+
         if ($this->colors) {
             $this->line = sprintf("\033[%sm%s\033[m", $this->styles['default'], $this->line);
         }