The coding you provided is working for me as well, however the coding that was working for me last week has stopped functioning. On hover, the URL shows at the bottom of the page, however when clicked nothing is happening (except when in the Layout pane, it works perfectly there).

This is the coding I was using:

<a href="https://www.google.com" target="_blank"><button style="color:black;background:radial-gradient(#FFFFFF,#E1FF9CD9);border-color:#65CD57;border-radius:5px;width:175px;height:85px;">Test Button</button></a>

If I recode everything to match the format used by Grant, that works as well. The strange part to me is that my coding was working (and is still functioning in the Modern Designer), but it has stopped working in the Classic Designer.

I have a "form" that is essentially a dashboard for our Finance Department, which has buttons to link to each form they might need to access for ease of use. Thankfully I built it in both designers so I was just able to swap it out for the time being, but in this case I prefer the classic as I can rename the browser tab so it doesn't just show as New Submission.

We have not touched anything related to how that HTML link should be clickable. My thinking right now is a browser update may have stopped this from working since you said it did work before. A couple of notes though.

1. nesting a button within an 'a' element is not valid HTML according to this spec
2. this would work despite being invalid if the button had type="button". On my classic designer reproduction clicking this button is actually just submitting the form

You should move your styles to the 'a' tag and make use of bootstrap's btn class to get the behavior you want:

<a
  href="https://app.laserfiche.ca/forms/cDj6k"
  target="_blank"
  class="btn"
  style="display:flex; align-items: center; justify-content:center; color:black;background:radial-gradient(#FFFFFF,#E1FF9CD9);border-color:#65CD57;border-radius:5px;width:175px;height:85px;"
>
Test Button
</a>