Not a bad config!

... AppGuard will block everything from installing which gives you a high degree of prevention but you can add VTZilla and an antivirus to improve your detection.
Are you using a trail for AppGuard or you have a full license?
VTzilla (Free) -
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VTzilla is a Mozilla Firefox browser plugin that simplifies the process of scanning Internet resources with VirusTotal. It allows you to download files directly with VirusTotal's web application prior to storing them in your PC. Moreover, it will not only scan files, but also URLs.
The scanning options are embedded in Firefox's context menu and download dialog, making the analysis process as easy as clicking a single button.
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