Adperastra

Adperastra is a free, open-source (MIT) file explorer for Windows 11. It brings browser-style tabs to your files: open independent folder tabs, and double-click a file to view it in its own tab without leaving the explorer. It has built-in viewers for images, PDF, text, code, Markdown, media and archives. The first preview release adds Office support: DOCX, XLSX and PPTX files open in a safe read-only preview, and you can then edit text directly on the page or in a spreadsheet grid and save a new copy, leaving the original untouched.