JavaScript on third party website

I am working on building a Chrome extension that injects bits and pieces of JavaScript onto websites, a bit like AdBlock does.

What is the best way to develop/test my JavaScript code on third-party websites? I want开发者_如何学C to have my custom JavaScript loaded as if it was JavaScript from the original website.

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You can use Chrome's developer console. Right click, go to inspect element, and go to console. Alternatively, press ctrl+shift+j.

You should write the code in notepad++ or a similar text editor and then copy it into the console and run it to test it.