LibreOffice is a private, free and open source office suite – the successor project to OpenOffice. It's compatible with Microsoft Office/365 files (.doc, .docx, .xls, .xlsx, .ppt, .pptx) and is backed by a non-profit organisation.
LibreOffice 26.2 also adds some experimental features such as BASIC IDE code completion, a new macro manager dialog, and ODF Wholesome Encryption. Downloads and more details on the LibreOffice 26.2 Alpha 1 release via the Document Foundation QA blog.