Developer credits
Git commits in Moodle 3.3.3 by Adam Olley
commit 3ff2f2d474d7e046a634fd354632a9e2092bcb9e Author: Adam Olley <adam.olley@blackboard.com> Date: Tue, 03 Oct 2017 07:46:18 +0800 Tag: v3.3.3 MDL-60320 icons: Use PNG icons as the preview thumbnails