U301 Url Shortener is now on Raycast. https://www.raycast.com/shiny/u301-url-shortener You can install this extension from Raycast’s store.

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Usage

Select an URL in any app, and use Raycast U301 command Shorten Url to shorten. The shortened URL would paste in place. If you’d rather to copy it into clipboard, change settings to Copy to Clipboard.
If you get an error that says Not able to get selected text, make sure you had turned raycast’s accessibility on:System Settings > Privacy & Security > Accessibility > Raycast

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Source Code

All Raycast extensions are Open Source.
You can find the source code here:
https://github.com/raycast/extensions/tree/main/extensions/u301-url-shortener