If you're looking for a solution that lets you customize error pages to help users with your React app, Bugpilot could be a good choice. Bugpilot is an error tracking service that offers a full platform for monitoring and debugging errors without requiring code changes or production dependencies. It features customizable error pages, a bug reporting widget, AI-assisted debugging with GPT-4, session recordings with browser logs for reliable debugging, and unlimited integrations with webhooks for notifications.
Another alternative is BoilerCode, which offers NextJs boilerplates to accelerate the development and deployment of SaaS and AI software. It's geared more toward offering prebuilt components and integrations, but BoilerCode's customizable boilerplates could help you get your app set up more easily and get to the development phase faster.
If you want a more comprehensive framework, Payload is a headless CMS and application framework written with TypeScript and React. It offers features like AI-generated content, visual editing and custom component integration that can be useful for building powerful and scalable apps. But its focus is on content management, not error handling.