So #Signal is supposed to be installed on a smartphone before you can use it on desktop? Unofficially, the desktop version is perfectly capable of creating new accounts. All you need is a number to receive an SMS or voice mail. Here is how.
Run Signal and press Ctrl-Shift-I to open Developer Tools (it's an Electron app). Switch to Console tab and enter the following command:
Use your actual phone number instead of +123456789.
If you prefer voice mail verification, use this command instead:
Disclaimer: The desktop client seems to lack quite a bit of functionality, so depending on your use case you might need a smartphone after all. For example, it seems that setting profile name and avatar isn't possible with the desktop client.
Things got considerably worse in the past years. The process of setting up a standalone desktop version of #Signal got more complicated and is broken even in the development version where it is enabled. There is a pull request to fix this which itself became broken.
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