Try this; Start Firefox in Safe Mode
While you are in safe mode;
Firefox Options > Advanced > General.
Look for and turn off Use Hardware Acceleration.

We're sorry to hear that Firefox is crashing. In order to assist you better, please follow the steps below to provide us crash IDs to help us learn more about your crash.

1. Enter about:crashes in the Firefox address bar and press Enter. A Submitted Crash Reports list will appear, similar to the one shown below.
2. Copy the 5 most recent Report IDs that start with bp- and then go back to your forum question and paste that into the "Post a Reply" box.

Thank you for your help!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

I would like to mention that I have been using the additional thurdebolt adapter to connect to the network.

I noticed that when the firefox started to hang the external hard disk (1TB Tunderbolt Lacie RAID) started to make noises like booting in a loop.

Possibly the report ID that I'm sending you are not related to this issue, because when I heard the "noises" I immediately interrupted the firefox process and the external drive seamed to have been "released" and stopped making the loop noises.

I have the same setup at home mirrored and the same unfortunately happened. So this is not an isolated case of one computer running crazy...

bp-9c61ec0f-9ba2-4b45-b82a-8a4532140517 bp-6e2bdea8-b11b-4b81-830d-3663f2140315

It could be the work of one of your add-ons, or even add / mal-ware. Look thru your add-ons list and make sure you know what each one is there for. Also, check the programs that are on your computer Go thru the list and use a web search to check any that you don't know what they are.