You can use the following third party application to get the Steam Base32 Authentication String.
https://github.com/Jessecar96/SteamDesktopAuthenticator
Once installed and setup, to get the shared_secret, open your SteamDesktopAuth folder and open 'maFiles'
Open the file with your steamID in Notepad and your Base32 code will be inside.
You can visit the following third-part URL for more tutorial to get Base32 encoded string.
Warning
Use at your own risk!
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