Comment 16 for bug 1840597

(In reply to Rob Wu [:robwu] from comment #8)
> I went to https://packages.ubuntu.com/bionic/web/firefox
> and downloaded the source package from http://archive.ubuntu.com/ubuntu/pool/main/f/firefox/firefox_68.0.1+build1-0ubuntu0.18.04.1.debian.tar.xz
>
> Inside that package, there is `debian/searchplugins/amazondotcom.xml` (and many other `amazon*.xml` files). They reference `resource://search-plugins/images/amazon.ico`.
> This file was removed in part 3 of bug 1496075, so any request to fetch that image URL will fail, and hence break `browser.search.get`.

Yep, simply deleting the Amazon engine without an icon fixed the issue. I'll let the user know.