The Norwegian fuel tank oveflow is not B787 specific. Saw it on other types, there are good technical explanations for it and I leave it to the secialists to reply .
What is far more worrying for me is the 2nd total loss of SSRs. Not only does the a/c becomes invisible to ATC ( as most new ATC systems are SSR only ) but also invisible to TCAS, the last safety net .
In both caes ( LOT last Sept and now here 2 days ago) the loss of SSR was detected by ATC , but one day it could remain undetected and a Brazilian scenario a la Gol/Legacy could repeat itself.
Not good .