Are all Google Chrome extensions open source by default?

Question

I want to know if i write a Google Chrome extension, will anyone be able to use my code?

Answer 1

Although the question has been posted long time ago, and received some answers (none accepted), I am adding my answer to complete previous answers.

Open-source, referring to software, refers to a «source code made available with a license in which the copyright holder provides the rights to study, change and distribute the software to anyone and for any purpose.» (source: Wikipedia)

Unless explicitly stated, software is copyrighted by the author. Even if you have access to sources, without an explicit permission, you can't read it. It's as if you find opened the door of a house; you have the ability to look into it and even walk in. But you don't have any rights to do it, and doing it is likely to put you in trouble.

Everybody can view source code of your extension because it's written in javascript. Nobody has the right to reuse, change and/or distribute your code without your explicit permission.

Moral of the story: never put any sensitive data in your extensions, because it's extremely insecure.

About Open Source, I suggest to read also the Open Source Definition by OSI