What is the ruling on a menstruating woman staying in the mosque, and is it permissible to use as evidence for its permissibility the fact that the woman who used to clean the mosque did not leave it when she menstruated? And what is the ruling on a menstruating woman sitting by the door of the mosque at its edges?

It is forbidden for a menstruating woman to stay in the mosque. This is the opinion of the four schools of thought and the fatwa of many scholars. The Prophet, peace and blessings be upon him, commanded menstruating women to abstain from the Eid prayer ground, which has the same ruling as a mosque. As for the woman who used to clean the mosque, it cannot be definitively stated that she remained inside it during her menstruation. A menstruating woman may sit outside the mosque, even next to the door, but it is not permissible for her to sit inside, as all of it is considered within the mosque's boundaries. However, she may stay in the mosque's courtyard or its unenclosed open area, as these do not take the ruling of the mosque.