diff --git a/Output/StreamOutput.php b/Output/StreamOutput.php
index b46f4d2ca..e94a5eb8b 100644
--- a/Output/StreamOutput.php
+++ b/Output/StreamOutput.php
@@ -90,7 +90,7 @@ protected function doWrite(string $message, bool $newline): void
     protected function hasColorSupport(): bool
     {
         // Follow https://no-color.org/
-        if ('' !== ($_SERVER['NO_COLOR'] ?? getenv('NO_COLOR') ?: '')) {
+        if ('' !== (($_SERVER['NO_COLOR'] ?? getenv('NO_COLOR'))[0] ?? '')) {
             return false;
         }
 
diff --git a/Question/ChoiceQuestion.php b/Question/ChoiceQuestion.php
index 0ccad051c..d062ce78d 100644
--- a/Question/ChoiceQuestion.php
+++ b/Question/ChoiceQuestion.php
@@ -25,14 +25,14 @@ class ChoiceQuestion extends Question
     private string $errorMessage = 'Value "%s" is invalid';
 
     /**
-     * @param string $question The question to ask to the user
-     * @param array  $choices  The list of available choices
-     * @param mixed  $default  The default answer to return
+     * @param string                     $question The question to ask to the user
+     * @param array                      $choices  The list of available choices
+     * @param string|bool|int|float|null $default  The default answer to return
      */
     public function __construct(
         string $question,
         private array $choices,
-        mixed $default = null,
+        string|bool|int|float|null $default = null,
     ) {
         if (!$choices) {
             throw new \LogicException('Choice question must have at least 1 choice available.');
diff --git a/Resources/completion.bash b/Resources/completion.bash
index 0d76eacc3..64c6a338f 100644
--- a/Resources/completion.bash
+++ b/Resources/completion.bash
@@ -17,7 +17,7 @@ _sf_{{ COMMAND_NAME }}() {
     done
 
     # Use newline as only separator to allow space in completion values
-    IFS=$'\n'
+    local IFS=$'\n'
     local sf_cmd="${COMP_WORDS[0]}"
 
     # for an alias, get the real script behind it