Today Opera beta updated to 42.0.2393.14. However, shortly after any page is loaded, it restarts. It did output the "send crash report" dialog. I'm not sure if I managed to send such, though.
Now the interface to send such a crash report would not load. Please let me know how to configure Opera to display it.
I do have the developer version installed too. It restarts immediately after loading.
The stable version 41.0.2353.46 operates normally.
The system runs Ubuntu LTS 12.04