Troubleshooter is an extension (those have the .xpi file extension) that you can install when you post a new question here. It's what inserts your comprehensive system information if you agree to that.

That is the addon installed from this support site to provide info (Addons, homepage etc. so we can fix a possible issue). Look at the "Question Details" menu to the left of your question and the More System Details to the for what the troubleshooter does.

well its not installed but its in my internet histroy so im a bit confused

Firefox does record history of addons you download too along your regular history.

It's possible that it only sticks around for the current session. You can check the following two places to see whether you still have it.

• Add-ons page / Extensions category
  
  orange Firefox button (or Tools menu) > Add-ons > Extensions

• Troubleshooting page
  
  Help > Troubleshooting Information > Extensions table