i have been informed that malware can be embedded within favicons

You have unfortunately been misinformed on this matter. From the perspective of web browsers, favicons are just images, and will never be executed as code. You might be thinking of web-application-specific exploits - e.g. related to vulnerable WordPress favicon plugins or something. This is not at all relevant to Perchance. Using this plugin is completely safe.

That said, I appreciate the concern!