Drupal 7.59 — "Pages not found"

Hello,

For a number of reasons I had to transfer my Drupal production system to a backup-test system (Test system base: Debian 9, Apache 2.4, MariaDB 10.1.2 (coming from MySQL 5.5!). On the production system everything works like a charm. The transfer included the Drupal root-directory tree plus the Drupal database. Now I have the following situation (after hours of googling, etc.!)… 

(1) The home page is found, but it is not displayed in its intended format (intentionally through a sub-theme based on bartik). Everything is displayed along the left edge of the page, vertically, one block below the other, no background image is shown.

(2) None of the other pages are found. Some pertinent definitions:
     – apache2.conf: root-dir: domain/drupal
     – rewrite definitions – as on the working production system
     – .htaccess file IS in the root directory and is employed (used the phpinfo() test “.htaccess”-file, as suggested for this test. It comes
       from the original install.

When I click on the respective URL at the bottom of my browser (Vivaldi) or look at Drupal’s watchdog table I can see that it wants to load URLs such as “http://domain/drupal/etc/etc“. I don’t know WHY, since the root-directory – as defined in the apache2 conf file – ALREADY includes the drupal-directory in its root definition.
I have no more ideas about how to solve this issue.  I imagine the whole issue is just some stupid error on my side. So, any help would
be greatly appreciated.

Regards
H. Stoellinger

Drupal version: 


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