What to include, depending on why you're writing
A bug report is fastest to act on with the exact page URL, the value typed in, and what you expected versus what you got — the more specific, the quicker it's reproducible. Trademark or brand concerns (about UIColor, Tailwind CSS, or any other referenced name) are covered in detail, including exactly what to send, on the Legal & Trademark Disclaimerpage. Requests about personal data — access, correction, deletion, or a general privacy question — are covered on the Privacy Policy, along with what this site actually stores (short answer: almost nothing, and only in your own browser).
Why there's no form
Every other page on this site runs entirely in your browser, with no request ever sent to a server beyond loading the page itself — a contact form would be the single exception, quietly sending whatever you typed to somewhere. Rather than add that exception, this page just lists a plain email address. It's less convenient than a form, but it doesn't require trusting a form backend with anything, and it keeps the "nothing you type ever leaves your browser" claim made throughout this site actually true, on this page too.