Do I need to install software on my PC?
No. Use the browser-based downloader and save the MP4 from your browser.
On a PC, the quickest workflow is to copy the Bluesky post URL, paste it into the downloader, and save the MP4 to your downloads folder.
Quick workflow
You want a local file for offline viewing on Windows.
You need to import a Bluesky clip into a desktop editor.
You prefer a web page over command-line tools or extensions.
No. Use the browser-based downloader and save the MP4 from your browser.
Your browser controls the save location, usually the Downloads folder unless you choose another path.