A CRX file is the extension format used for Google Chrome browser extensions. Essentially, it’s a compressed package containing all the files needed to install a browser add-on—in this case, the ZenMate VPN.
If you must install a CRX file for testing, you can do so by going to chrome://extensions/ , enabling Developer Mode , and dragging the file into the window. However, this is highly discouraged for security tools like VPNs. Zenmate Vpn Crx File