I suspect it’s cached in your local browser ( unless you have more than one server). I’m not getting a redirect.
If you previously had a “permanent” redirect, then your browser would remember that, and continue to redirect. Can you try on a different browser / computer ?
Whether you want to redirect all to the “www” version of the “non-www” version is a personal choice, there is no real difference between the two as far as I’m aware (although it is best to redirect all to the same one, whichever you choose )
Yes, it’s a personnal (and historic) choice, I’ve set all canonical with www but I prefere make a clean job and also serving www. pages.
Very strange : I cant set any htaccess anymore (since https) even with just one simple line like "ErrorDocument 404 /error.php"
That give me an error 500 each time