I built OneToolBox — free browser-based tools for developers

Hey devs👋 I've been building OneToolBox: https://onetoolbox.dev/ It's a collection of free web utilities for developers and creators — JSON tools, YAML validation, hash generation, text diffing, image tools, converters, and more. The main idea is simple: do as much as possible directly in the browser, without requiring accounts or uploading users' files/data to a server. I'm still actively improving it, and I'd really appreciate feedback from developers here. What would you improve? Which tools are missing? Are there tools you use regularly that you'd like to see added? Any UX problems or annoying workflows? Is there anything you'd change about the interface? Are there performance, privacy, or technical improvements you'd recommend? I'd especially appreciate criticism from people who actually use developer utilities regularly. Don't hesitate to point out what's bad or unnecessary — that's more useful to me than compliments. If you have a minute, take a look and tell me w