The ideal solution is that the page has a canonical tag, telling search engines what the main URL for the content is: https://ahrefs.com/blog/canonical-tags/. I don’t know if Lemmy already does this […]

I checked and it does, this post’s canonical is:

<link data-inferno-helmet="true" rel="canonical" href="https://merv.news/post/26663">

Weirdly it uses OP’s instance, in this case merv.news. Shouldn’t it be the instance where it was posted?