Could not find a way to get the the database connection string - Drupal's $db_url with drush. 
 

bin/drush status --fields="db-driver,db-hostname,db-port,db-username,db-password,db-name" --format="json" | jq '."db-driver"+"://"+."db-username"+":"+."db-password"+"@"+."db-hostname"+":"+."db-port"+"/"+."db-name"'

Favicons are a big thing again, as every mobile browser reinvents the wheel and in it's own genious and individual way. Try to solve the favicon-quiz on css-tricks.com. You will have fun. 

The easiest way is to use a favicon generator like realfavicongenerator.net and check the result using a favicon checker.

Locally I use MAMP on my Macbook to develop Themes for Drupal. There's a nice module called backup & migrate which you can use to get the relevant tables from your Drupal installation.