grpc-protobufjs-devtools is a free Chrome extension developed by ttshangxiang. It falls under the category of Browsers and is classified as an Add-ons & Tools subcategory. This extension allows users to create proto.js files using Node.js and protobufjs, and mount JSON strings to the window.

To use grpc-protobufjs-devtools, users need to follow two steps. First, they need to create the proto.js file using Node.js and protobufjs. This can be done by using the provided code snippet, which imports the necessary modules, specifies the path to the proto files, and generates the proto.js file. Second, users need to mount the JSON string to the window by using another code snippet. This allows the JSON string to be accessible in the browser.

By providing these functionalities, grpc-protobufjs-devtools simplifies the process of working with proto files and JSON strings in the Chrome browser. It is a useful tool for developers who are working with gRPC, proto, protobufjs, and Chrome extensions.