Hello,
There might be a certain incompatible add-on you are using which causes this. Go to Tools >> Add-ons and disable every add-on one by one.
The extension you most recently enabled is either bad, or conflicting with another extension you enabled earlier. To find out if it's a conflict, enable ONLY that extension, and see if you can reproduce the crashes. If you cannot, then enabling other extensions until you crash will help you find the conflicting extension.