Lexical Developer Tools от Lexical

Adds Lexical debugging tools to the Firefox Developer Tools.

Lexical Developer Tools is a Firefox DevTools extension for the open-source Lexical JavaScript text editor framework.
It allows you to inspect the Lexical state in the Firefox Developer Tools.

This extension requires permissions to access the page's Lexical state, but it does not transmit any data remotely.
It is fully open source, and you can find its source code at https://github.com/facebook/lexical/tree/main/packages/lexical-devtools.