Dosson

Performance and usage, DOS style

Dosson puts a keyboard-driven, DOS-style inspector on top of any web page. Press Esc twice, or click its toolbar icon, and a retro menu opens over the page. Press Esc twice again and it's gone. PERFORMANCE See the Core Web Vitals of the page you're on and how long its main thread was blocked, then what the page weighs: how much it downloaded and of what kind, how large and deep its DOM is, and how many CSS rules it carries. INSPECT Browse the variables and functions the page added to the global scope, grouped by type. Open any object to explore it, change a value in place, or run a function with your own arguments. Iframes are listed too, including cross-origin ones, each with its own variables and functions. FRAMEWORKS Find out which JavaScript and CSS libraries the page is built with, which version of each it loads, how each was detected, and how far behind the latest release it is. SECURITY Spot credentials that any script on the page could read, such as API keys and tokens left in global variables, browser storage or readable cookies. Values stay redacted until you choose to reveal one. KEYBOARD FIRST The arrow keys, Enter and Esc drive everything. Press ? in any menu for help, or x to export it as JSON. In Settings you can change the show/hide key and the text size. PRIVATE BY DESIGN No server, no analytics, no account. Everything is read and computed in your browser and forgotten when you close the tab. The only network request Dosson makes is to look up a library's latest version, and only when you open that library's details. Privacy policy: https://bocares.com/dosson/privacy/