Plenilunio
Lab Technician
Maybe it's because you haven't reached 50 posts? I don't know about the image signatures, but you can't upload an avatar until you've written 50 posts and been a member for two weeks.
Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
It won't work for you in the main message section because you haven't been a member for at least two weeks and have 50 posts or more. It should let you put that in your signature section for a banner. Copy and pasteIt doesnt want to work still ="(
You have to choose if you want a banner OR text, but not both.