Remove the error handler at the end of a run, fixes #5340

src/Composer/Console/Application.php

@@ -228,9 +228,12 @@ class Application extends BaseApplication
                 $io->writeError('<info>Memory usage: '.round(memory_get_usage() / 1024 / 1024, 2).'MB (peak: '.round(memory_get_peak_usage() / 1024 / 1024, 2).'MB), time: '.round(microtime(true) - $startTime, 2).'s');
             }
 
+            restore_error_handler();
+
             return $result;
         } catch (\Exception $e) {
             $this->hintCommonErrors($e);
+            restore_error_handler();
             throw $e;
         }
     }