Sitecake - Drag and drop CMS for HTML websites. It's flat file CMS so it's pretty fast.
Clover Sites - Clover Sites is a powerful, intuitive, and affordable content management system and website builder that enables you to create your online presence within no time.
ClassicPress - The WordPress fork. No Gutenberg. Great future!
Rocketspark - Rocketspark is an online website builder that allows you to have a website in just minutes that is fully optimized for search engines.
TYPO3 - TYPO3.com - Infos, SLAs, Extended Support Versions and more
Webador - Webador is a website-building software that is designed to help businesses create personalized websites and online stores with custom domains, themes, content, payment processing systems, and more.