change_backlink

Hello,
I want to post an external link in the footer of the page, but it adds my domain in the link.
I found this solution in the last answer –
https://kriesi.at/support/topic/add-a-link-to-an-external-link-in-footer/

but can’t get it to work in colormag
how to create the link?
Can you help please?
thank you.

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