Steps to reproduce
Run yarn install && node app.js
Open a browser and head to http://localhost:8080
Result: index within {#each} is undefined when used within an element attribute.
Using svelte-cli to compile component like so:
svelte compile --format iife src/components/IllustratedForms.html -o public/js/IllustratedForms.js
https://svelte.technology/repl?version=2.9.1&gist=f9dddf6f11b3ab005a214d24059a6826