• Adds information about the current language on the Languages panel
• Reduces the chance that Query Monitor blames itself for PHP errors that don't have a stack trace
• Replaces the use of Dashicons with inline SVGs and removes the dashicons dependency
• Switches to class autoloading via Composer for reduced memory usage
• Changes the priority of the shutdown dispatcher from 0 to PHP_INT_MAX to ensure as much data as possible is collected
• Improves the styling of Debug Bar add-ons
• Fixes some erroneous localisation of float values in REST API output
• Bumps the minimum supported PHP version to 5.6
• Improves various other bits and bobs