Thunder is a Drupal 8 based distribution.
We are working on GitHub and drupal.org. Issues will be managed on drupal.org. That gives us the possibility to better interact with related issues. Code improvements will be managed over GitHub's PR system.
If you found an issue with Thunder, please open a ticket on drupal.org. Please have in mind that Thunder is a collection of Drupal modules, a set of configuration and very little custom code.
So, if you can track down an issue to a specific module, please open the ticket in the corresponding issue queue on drupal.org.
If you want to open a PR for the Thunder distribution, please make sure you created an corresponding issue on d.o. before. All created pull requests should contain a d.o. issue number in it's title.
Please also note the pull request template to create better quality pull requests.