ADVENT CALENDAR PUZZLE 17

Solution:

• EMOJI CODE: Follow the link and use the water droplet emoji💧to decode.
• JAB code: Search for color QR code online. A similar code can be found on the Wikipedia page of QR Codes. Use this website to decode, you get a mnemonic whose order is reversed (the filename was a hint).
• HIDDEN SEED: The HTML source of the page is hiding a seed somewhere.