I feel like I'm going crazy but alert() and console.log() refuses to work anywhere on Firefox 26.

At first I thought it was my own website's problem, but I cannot for the life of me to get it to work via javascript: urls, Firebug, I even tried it in jsfiddle.net by just putting alert('test'); in the script panel.

Tried uninstalling and installing again, no luck.

The only extension I'm running is Firebug.

Heck, Stackoverflow didn't even prompt me about leaving when I accidentally clicked the back button while writing this.

Also yes, I made sure there was some content inside the alert() and console.log()

What I mean by not working is that Firefox treats the code as if it were non-existent, nothing happens.

Once again, here's my environment:

Browser: Firefox 26.0

OS: Windows 8.1 Pro

Issue: alert(), console.log(), and apparently prompt() doesn't work

If anyone might know why this is happening, I would highly appreciate an answer.

UPDATE

Following Pointy's comment, it appears that both alert() and console.log() work as expected on the New Tab Page, but nowhere else