If you are on the website, you have a couple of options. First, the help ? menu > Report a Bug
That will create a screenshot of what you are seeing, you can mark up the page with some provided tools, and fill out a comment about what you think is wrong or what should changed.
You can also open a ticket: https://support.chess.com/customer/portal/emails/new and choose either Suggestions (or maybe Technical depending on what you are reporting).
If you are on the app, Settings > Report a Problem
Maybe I missed it but I can't find a place to report bugs or ill-advised "features". Is there such a place?