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CONTRIBUTING.md

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+# Contributing
+
+When contributing to this repository, take this into consideration:
+
+- You can add your own extension to our list once it's ready. Your extension doesn't need to be 100% completed, but try not to open a Pull Request if we are not able to see what the extension is about.
+- If you add someone else's extension we might not be able to merge it.
+- We are thankful for all Pull Requests fixing typos, however, these Pull Requests will not count towards the Hacktoberfest goal.
+
+## Pull Request Process
+
+1. Ensure the extension you add is OK with being added to this repository.
+2. Update the README.md with the details of the extension.
+3. We will review your Pull Request in no more than 2-3 working days.
+
+## Review Process
+
+We might install and test the extension you add to this repository. If we cannot find on either the Pull Request or the extension code any description of the use case for this extension, be aware we might not be able to merge your Pull Request. Nevertheless, we will contact you via Pull Request comments and ask you for these details.