Please update Iceweasel to the version 60, which is based on Firefox Source code update.

The highlighted features that it haves are:

1.- Added a policy engine that allows customized Firefox deployments in enterprise environments, using Windows Group Policy or a cross-platform JSON file.
2.- Redesigned Cookies and Site Storage section in Preferences for greater clarity and control of first- and third-party cookies
3.- Applied Quantum CSS to render browser UI
4.- Added support for Web Authentication API, which allows USB tokens for website authentication.
5.- Enhanced camera privacy indicators: Firefox now turns off your camera and the camera's light when you disable video recording, and turns the camera and light on when you resume recording.
6.- Added an option for Linux users to show or hide page titles in a bar at the top of the browser. You’ll find the Title Bar option in the Customize panel available from the main browser menu.
7.- Improved WebRTC audio performance and playback for Linux users.
8.- On-by-default support for draft-23 of the TLS 1.3 specification.
9.- TLS certificates issued by Symantec before June 1st, 2016 are no longer trusted by Firefox
10.- Bookmarks no longer support multiple keywords for the same URL unless the request has different POST data.
11.- Updated the Skia graphics library to milestone 66.

And some special mention to thechanges applied to "New Tab/Firefox Home" section:

1.- Responsive layout that shows more content for users with wide-screen displays.
2.- Highlights section includes web sites saved to Pocket.
3.- More options to reorder sections and content on the page.
4.- Pocket Sponsored Stories will appear for a percentage of users in the US. Read about our privacy-conscious approach to sponsored content.

For more information, please follow this link: https://www.mozilla.org/en-US/firefox/60.0/releasenotes/

Thanks.