You can try these steps in case of issues with web pages:

You can reload web page(s) and bypass the cache to refresh possibly outdated or corrupted files.

• Hold down the Shift key and left-click the Reload button
• Press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
• Press "Command + Shift + R" (Mac)

Clear the cache and remove cookies only from websites that cause problems.

"Clear the Cache":

• Firefox > Preferences > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems:

• Firefox > Preferences > Privacy > "Use custom settings for history" > Cookies: "Show Cookies"

Start Firefox in Safe Mode to check if one of the extensions (Firefox menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

• Switch to the DEFAULT theme: Firefox menu button/Tools > Add-ons > Appearance
• Do NOT click the Reset button on the Safe Mode start window

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

Reply posted in another thread.

• [/questions/1088265]

Hello When I open TLS it close after 2 seconds 
http://www.the-tls.co.uk/tls/
Instead I get a error-message 404.
Why.
Works with Safary and Opera
Thanks for an answer

Did you try my above suggestions?

Sorry, you can ignore that suggestion. I missed that you are on Mac.

<strike> Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) to see if that has effect.

• http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/
• http://www.7tutorials.com/4-ways-boot-safe-mode-windows-10</strike>

I see some references to the clicktale in some JavaScript files, so make sure that you do not block these requests. The clicktale website seems to be used as a CDN to store additional files.

• http://tags.tiqcdn.com/utag/newsinternational/thesundaytimes/prod/utag.21.js?utv=ut4.008.201409160833
• http://cdn.clicktale.net/www/WRe0.js