No worries.
If you don't want the forum software to work its magic on your link text, wrap it in angle brackets.
This markup:
has URL <https://create.arduino.cc/getting-started/plugin/download>, and won't scroll
renders like this:
has URL https://create.arduino.cc/getting-started/plugin/download, and won't scroll
The "onebox" link preview thing is occasionally cool, but I have never found value in the inline link text replacement the Discourse forum software does. I find myself doing the angle bracket wrapping trick more often than not nowdays.