Referring to a variable from a URL

Newbie here :slightly_smiling_face: I have successfully added a variable to a URL. The resulting URL looks like this…

…#control=Animals_Detail%202&uid=c4ba98f6&page=detail

On the resulting page (Animals_Detail 2) I have an action that I want to add “uid=c4ba98f6” onto the end of. How do I reference the variable uid and it’s value in an action?

For the record, this doesn’t work…

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