I have just discovered through reliable sources that the popular Hippo viewer records and transmits personal information (including MAC address) to an unknown destination without the user's consent.  This is very dangerous and considered an ethical violation at the very least.  One can only wonder what purpose  Mana Janus  has with this data.

From the source....

"

When the viewer is started, it automatically checks if a new version is available. For that purpose, it transfers the viewer product name, viewer version number, viewer channel, platform and MAC address to a web server. No other data is transferred.

Each MAC address is regarded as a unique user, which is not completely accurate, but should be close enough. The MAC address is transferred and stored only to enable the statistics shown on this page.

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