Fatal error: Uncaught Error: Class 'JsonSchema\Validator' not found in /home/stainlessexhaust/public_html/vendor/composer/composer/src/Composer/Json/JsonFile.php:173 Stack trace: #0 /home/stainlessexhaust/public_html/vendor/composer/composer/src/Composer/Factory.php(290): Composer\Json\JsonFile->validateSchema(1) #1 /home/stainlessexhaust/public_html/vendor/composer/composer/src/Composer/Factory.php(576): Composer\Factory->createComposer(Object(Composer\IO\BufferIO), '/home/stainless...', false) #2 /home/stainlessexhaust/public_html/vendor/magento/framework/Composer/ComposerFactory.php(47): Composer\Factory::create(Object(Composer\IO\BufferIO), '/home/stainless...') #3 /home/stainlessexhaust/public_html/vendor/magento/framework/Composer/ComposerInformation.php(362): Magento\Framework\Composer\ComposerFactory->create() #4 /home/stainlessexhaust/public_html/vendor/magento/framework/Composer/ComposerInformation.php(375): Magento\Framework\Composer\ComposerInformation->getComposer() #5 /home/stainlessexhaust/public_html/vendo in /home/stainlessexhaust/public_html/vendor/composer/composer/src/Composer/Json/JsonFile.php on line 173