Hey there thank you for posting in the Lucid community! Our sincere apologies for the delayed response on this thread - I wanted to follow up in case this answer may still be useful to you and to provide a solution for other users who see this thread in the future.

Unfortunately removing custom colors from the color picker is not currently supported in Lucidspark. However I certainly can understand the need to do so and we're always looking for ways to improve Lucidspark; your feedback is the best way for us to do that! I've gone ahead and submitted your idea to our product team on your behalf and it will be taken into consideration when prioritizing improvements to the product.

For anyone else with a similar request: please add your feedback and details about your use case to this thread in order to voice additional support to our development team. Thanks for your request!

Hi Everyone! Just wanted to jump in here with a workaround- if the custom color is not in use anywhere in the document, the page can be reloaded and the color should be removed automatically from your color palate.