Hi Matthias
RawTherapee is optimized to make the most of your CPU and RAM. It is not
optimized to freeze your system. What most likely happened is that you
simply ran out of memory, having Firefox with all its tabs open while
processing a raw photo, so your system started moving data to swap. Keep
all RAM-hungry programs closed while processing raw files. Also, please
use the latest snapshots Philip offers, because there have been a
tremendous number of improvements since the two year old 4.2.0 you're
still using.
Kind regards
Morgan
