Please update to 59.0.2 https://support.mozilla.org/en/kb/update-firefox-latest-version Please consider turning on send info to Mozilla from with in Firefox before posting a question. This helps us help you. I have no info from your system that would help see things that cause issues. Please let us know if this solved your issue or if need further assistance.

Separate Security Issue: Update your Flash Player or remove it using these links; http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html Uninstall Flash Player | Windows http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-mac-os.html Uninstall Flash Player | Mac '''Note: Windows users''' should download the '''ActiveX''' for ''Internet Explorer.'' '''and''' the '''plugin''' for ''Plugin-based browsers'' (like Firefox). '''Note: Windows 8 and Windows 10''' have built-in flash players and Adobe will cause a conflict. Install the plugin only. Not the ActiveX. Flash Player Version: '''Version 29.0.0.113 ''' https://get.adobe.com/flashplayer/ Direct link scans current system and browser '''Note: Other software''' is offered in the download. <Windows Only> https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, Win IE . . . .) '''Note: Other software''' is offered in the download. <Windows Only> +++++++++++++++++++ See if there are updates for your graphics drivers https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration