I understand the www and non-www canonical can be set in the .htaccess file. Is it then important to again verify the same on Search Console with both www and non-www versions verified? For example, I see both the properties verified within the search console for a new website I was given access to.
Long version: perversely, the only way you can tell them you only want to use one form is if you verify both forms.
Still longer version: not sure what you meant about "canonical" and "htaccess" in the same sentence. You should redirect to your preferred form. The "canonical" locution is for when redirecting is out of your power.
Yeah, I hate that. It clutters things up, but that's just how it is.
That said, if you have everything set up correctly (i.e. 301 redirects from non-canonical to canonical), there's no real need to explicitly say that you own both by claiming both. Google will figure it out.
>>not sure what you meant about "canonical" and "htaccess"
He means properly redirecting from non-canonical to canonical via .htaccess directives so that Google knows what your canonical URL is. As you say, you generally shouldn't need a rel=canonical if there is only one possible URL on your site that returns a 200 for that page.
Not to be argumentative but I've never verified both and after 17 years I've yet to have an issue. I know everyone keeps saying I need to do this, but I have yet to see any evidence regarding my site. If I do, I will :)
Wait... I didn't say you have to. I said if you have it set up right, you shouldn't have to. Completely agree with you.
If you want to tell Google specifically via Webmaster Tools that the www version is the canonical and the non-www is not, then you DO have to register both, but if you have your redirects set up right, there is no reason that you should need to tell this to Google.
I don't, anymore. Or rather - if I'm changing from one to another for some reason, I will add them both, but if it's a new site, or there's no changes, I don't bother. I know how to do my redirects correctly.
You would still need to verify both. Particularly if you have to deal with a backlink penalty of some sort, which I hope you won't have to.
The links reported by www and non-www versions in search console need not necessarily be the same. One would need to compile links by collating both non-www and www version backlinks for disavowing links.