Statamic - Build better, easier to manage websites. Enjoy radical efficiency. It's everything you never knew you always wanted in a CMS.
Sitecake - Drag and drop CMS for HTML websites. It's flat file CMS so it's pretty fast.
HubSpot Website Platform - HubSpot Website Platform is a content management system that enables marketers to build websites personalized for every visitor.
ClassicPress - The WordPress fork. No Gutenberg. Great future!
Craft CMS - Content management system built on Yii PHP Framework
TYPO3 - TYPO3.com - Infos, SLAs, Extended Support Versions and more