When I press the "open new tab" button, nothing happens. What can I do?
Try the Firefox SafeMode to see how it works there.
A troubleshooting mode, which disables most Add-ons.
Troubleshoot Firefox issues using Firefox SafeMode
When in Safe Mode...
To exit the Firefox Safe Mode, just close Firefox and wait a few seconds before using the Firefox shortcut (without the Shft key) to open it again.
If it is good in the Firefox SafeMode, your problem is probably caused by an extension, and you need to figure out which one.
When you figure out what is causing that, please let us know. It might help other user's who have that problem.
i have the same problem, when i open some sporty websites such as www.espn.com , www.nowgoal.com, www.hupu.com .. open new tab is not work
I restarted in "safe mode" as described and went one by one through the add-ons.
For me it was the "Ask Bar" once that was gone the New Tab Button works again.