Creator here - this was much more technically difficult than it seems, because rendering pixel perfect backgrounds with scaling width is non-obvious. Hit 'Esc' and you can set some options, including changing the background pattern.

If you want to see a big file, I have a direct link to load the Blocktronics WTF4 ANSI which is over 4000 lines: https://sure.is/ansi/?wtf4=1

Wow nice. Is there a fastscroll in mobile?

This is very cool! And I say that as someone who was in iCE in the early 1990s ;)

The baud scrolling and SAUCE support are nicely done, and "drag a zip here" is top-tier magic, though when I tried dragging in an old iCE pack's zip file, it only showed one ANSI inside there; I was expecting a file picker.

Feature suggestions: "Show invisible text" toggle and an option to switch between 16-color background mode and 8-color background mode with blink support. You're already parsing the SAUCE which has an "iCE colors" boolean; you can use this to control the default for the latter setting.

Details: https://forum.16colo.rs/t/ice-colors-or-blinking-text/27

Really I'd love to see animations from https://en.wikipedia.org/wiki/TheDraw work.