Localhost/nextcloud 404 Not Found and 403 Forbidden on Pop!_OS 20.04 after Nextcloud Snap installation

Trying to install Nextcloud Snap on Pop!_OS 20.04, and I’m stuck on the initial configuration step.

Right after I installed Nextcloud I went to check out local links described in documentation. localhost is showing Apache2 Ubuntu Default Page, but localhost/nextcloud was responding with 404 Not Found.

After some digging I figured out that Nextcloud Snap incorrectly configured /etc/apache2/sites-available/nextcloud.conf on installation (maybe it’s because Pop!_OS doesn’t support Snaps out of the box).

I modified every /var/www/nextcloud/ in the config to /var/snap/nextcloud/, because this is where Nextcloud files are located in this case. “404 Not Found” changed to “403 Forbidden”. And remains 403 even after sudo chown-R www-data:www-data /var/snap/nextcloud.

How do I troubleshoot it further?