[Affected versions]: Firefox 54.0a1 (2017-02-22) [Affected platforms]: Windows 10 64-bit Ubuntu 16.04 32-bit [Steps to reproduce]: 1.Launch Firefox with clean profile. 2.Create extensions.webextPermissionPrompts and set it to true. 3.Restart the browser. 4.Navigate to Add-ons Manager -> Extensions and search for the following keyword: e10s. 5.Install the second result: “amo e10s”. [Expected Results]: A webextension with no icon specified in manifest.json displays the puzzle icon in search results list during the installation process. [Actual Results]: No puzzle icon is displayed in search results list while permissions pop-up is displayed for a webextension with no icon specified in manifest.json. (see attached screenshot) [Additional notes]: To be noticed that this issue is also reproducible while installing legacy add-ons but is not so visible because there is no doorhanger that delays the installation process: https://www.screencast.com/t/7f81lqwQdC

Updating the title to match the description in comment 0. And since this is an existing bug unrelated to permissions, removing the blocker on permissions.

This is no longer relevant since bug 1263313 landed.