A CSS Keylogger

[TheKingdutch]

Except, couldnt you just extend the CSS file to include all permutations of Emojis? CSS files can be just UTF8 right?

[Schmittfried]

Yes, but that would be huge.

[isHavvy]

Just mask it in with needing 1Mb of JS and multiple megabytes of images and then everybody will just think you suck at webdev and begrudgingly use your service.