Hi there,
Sorry to hear you're having trouble installing the add-on. The error message "Installation aborted because the add-on appears to be corrupt" usually points to an issue with the Firefox browser itself rather than the extension.

Please try updating to the latest version and try to refresh firefox (https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings) and then attempt the installation again. The extension is installing and working fine for other users, so this should resolve the issue.

If the problem persists, feel free to reach out with more details and I will be happy to help troubleshoot further.