This is a reproducer for sulu/sulu#7713

What did I change:

• Basically, I changed the docker compose config a bit to run it without a local PHP installation.
• I added the line containing "save_path" (line number 11) at config/packages/framework.yaml

Steps to run:

• Run docker compose up -d
• Run docker-compose exec php bash
• Run php -dmemory_limit=4G /usr/local/bin/composer install
• Run bin/console sulu:build dev --no-debug
  • Confirm with Look good? (y) with y
• Open web browser
• Open URL http://localhost/admin
  • Use credentials admin / admin to Login
• Click on the burger menu on the top left
• Click Webspaces
• Hover Website in the list with the mouse
• Click on the pencil icon
• Look at the preview on the right side
• An error is shown
  • Warning: ini_set(): Session ini settings cannot be changed when a session is active
  • )