**Acceptance Criteria:**
* When a request for an ebook export results in an error for a user (i.e., both via download button & side-links -- but preference for download button, if only one, they should):
** Be redirected to the Wikisource Export page (if they are not there already)
** Display "Download error" as default message
*** Note: This is TBD based on discussion with engineers on how much information we can share based on specific error vs. a more generalized message to cover all cases
** If the user clicks on "Learn more," the error header will expand & provide recommendations on how to download the book again, which will be written as follows:
*** Please try these steps if you encounter an error:
*** 1. Try to download the book again.
*** 2. Try to download the book as an EPUB file.
*** 3. Check the box in "Options" to remove credits.