Best approach (IMHO) is to work around it - think outside the square (No pun intended).
This works for me: https://viemedia/home
No system is perfect and no system will give thew user everything they need; and that comes from over a decade working on Drupal, Joomla, Wordpress*, and more recently SquareSpace.
From Google themselves.... possible solutions:
Redirects: A strong signal that the target of the redirect should become canonical.
rel="canonical" link annotations: A strong signal that the specified URL should become canonical.
Sitemap inclusion: A weak signal that helps the URLs that are included in a sitemap become canonical.
The one stands out, for me, is to do a redirect. BUT, as a redirect via SquareSpace is only possible for URL that don't exist, then a CDN is needed, I use Cloudflare and simply add a Rule for URL forwarding.
Simple.
The second option is to add a rel="canonical" link to the Page Setting (Advanced), in Page Header Code Injection.
The answers are out there, you just need to ask Google, if the forum is not forthcoming :)