Trace - Visualized Node.js monitoring
Fiddler - Fiddler is a debugging program for websites.
WeBlock - Weblock allows you to block online content.
Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
SponsorBlock - SponsorBlock is an open-source crowdsourced browser extension to skip sponsor segments in YouTube videos.
HTTP Toolkit - Beautiful, cross-platform & open-source tools to debug, test & build with HTTP(S). One-click setup for browsers, servers, Android, CLI tools, scripts and more.