JSFiddle - React, Tailwind, and code Playground
JavaScript
if (/[A-Z]/.test(before[0])) {
after = after[0].toUpperCase() + after.substring(1, after.length);
}
if (/[A-Z]/.test(before[0])) {
after = after[0].toUpperCase() + after.substring(1, after.length);
}