The CR-Unblocker will get an American Session ID and sets it as your current Session ID cookie. Like this Crunchyroll will think you are located in America and therefore you should have access to all anime you couldn't watch.
The method CR-Unblocker are using is basically the one described above. Your session id is bound to your account after being set as a cookie. However, we take security very seriously. If you notice anything suspicious PLEASE tell us.
Please note: We are not responsible for any compromised accounts.
Click on the extension's icon and check "Save login credentials". The next time you log in, your username and password will be stored locally in encrypted form and then used to log you in when switching regions. If the checkbox is not checked, no data will be stored.
You can just install the Firefox Extension (also working on Android) from here.
Unfortunately the Chrome and Edge Stores have removed the unblocker from their stores, reuploading would probably not work so this option will no longer be there.
Alternatively you can just download the source and package it yourself. The extension is tested in Firefox, but it should also work in all other browsers supporting WebExtensions API.
To pack the extension for the extension store you need to follow these steps (on linux, windows may be different):
npm run-script build
If you are really concerned about security you can run it yourself. Up to date instructions can be found in the backend repo.
The repo for the server backend is here.
The extension is always under development. Some features might be added later. If you have any idea on what to add feel free to contribute to the project or open an issue.