getExtension() to Lib:getExtension() in Bolt\FilePermissions
getExtension() to Lib:getExtension() in Bolt\Config
getExtension() to Lib:getExtension() in
Bolt\Configuration\LowlevelChecks
getExtension() to Lib:getExtension() in Bolt\Controllers\Backend
getExtension() to Lib:getExtension() in
Bolt\Provider\TranslationServiceProvider