Yesterday, I noticed that "Alt+R" wasn't working. Anywhere. Other key combinations with Alt were working normally.
So I fired up Eclipse, went to keyboard shortcut settings and saw that I can't map "Alt+R" to anything. From these findings it was obvious that something, somewhere has globally registered this key combo.
After some trial and error, I found a non obvious thing: when Chrome is launched, the combo doesn't work. When it's closed, it works. It turned out a certain Chrome Extension was trapping this very combo. After disabling it, everything was back to normal.
Now, I'm wondering, is there a tool or utility that could help me pinpoint problems like this in the future? Something that says "this key combo is being intercepted by application or process XYZ"?