Feature Request for Codex: Codex Customization via Prompting

Wouldn’t it be cool to customize codex GUI via prompting, so that it can extend itself? e.g. “I want a toggle button for night mode in the top right of the navigation bar”. Would be interesting to see what people come up with. It could happen in a way that such extensions can be staged for review by openAI, and, if found helpful, can be pushed to codex in general.