If you encounter a bug on the forum, then it is best to report a bug.
Before submitting a report
Before you do, you should try to reproduce the bug if possible. If the bug comes up again, then these are your reproduction steps.
Next, you should try to reproduce the bug in the official support forum, https://meta.discourse.org. If you can reproduce the bug, then the bug can safely be reported.
If you cannot reproduce the bug, then it is likely an issue with this forum instead, not a Discourse issue. You should tell staff if that is the case.
Writing a bug report
- don’t have an account on that forum? make one, through the login page: Discourse Meta - The Official Support Forum for Discourse
First, you want to post a topic in the bug report category of Discourse Meta.
If your bug is purely visual, than it will fit better in the UX category of Discourse Meta.
Be sure to write down the description of the bug, and steps to reproduce the bug. These are steps to making a bug report. You should also write the expected behavior that should have happened. Keep a polite tone when creating a bug report, or you will be ignored. You should also read this topic: Writing a Good Bug Report - users - Discourse Meta
What happens after?
When you submit the topic, then the bug will be sent to the staff of Discourse for them to investigate. Please be patient while they fix the bug.