Destiny 2 Fall of Osiris comic is now available to read online for free and it comes with a hidden emblem.
You can read the full comic here: https://comics.bungie.net/
To redeem the hidden emblem, go to https://www.bungie.net/redeem and type in xfvkhpn97 to unlock the new Visionary emblem. The code comes from the hidden morse code at the end of the comic. Once you have redeemed your code, go to the Vault and then Collections to see your new emblem.
Source: Taken from Reddit, /u/TheyKilledFlipyap’s thread.