Is it ok to attach a html (only html and css, without js) file containing a short quickstart of the application?
I already have a html for other purposes and it fits very well for reviewer to better undestand the application.
Supported filetypes are .pdf, .doc, .docx, .rtf, .pages, .xls, .xlsx, .numbers, .zip, .rar, .plist, .crash, .jpg, .png, .mp4, or .avi.
I would advise simply copying and pasting the text in the input box. If you do not want to, you could simply save the HTML page as PDF and attach it.