Is it permissible for a woman observing the 'iddah (waiting period) after her husband's death to move from the house of 'iddah to another house?

The basic principle is that a woman observing the 'iddah (waiting period) after her husband's death should not move from the house where she received the news of his passing. However, she is permitted to move if she fears harm by remaining there, based on Allah's saying: "And He has not placed upon you in religion any difficulty." Old harm is like new harm.