To open a new issue, head over to any project, click on the Issues tab and then on the New Issue button.
Make sure that you give your Issue a descriptive Title that will help others understand it at a glance. In the description, it helps to break down the Issue and provide context.

Note: It might be worth checking before creating a new Issue whether another similar Issue was created before. For this, take a look at the Closed Issues list below Open Issues if there are any.
Learn all about Issues
Discover all you can do with your Issue feature: