Is it permissible to trade currencies online using the margin system or facilitation, where the difference between buying and selling is paid to the broker, there are no usurious interests on the facilitation, and the facilitation is not required to be repaid at a specific time, knowing that the facilitation is not received physically and can only be used for trading currencies? And is this facilitation considered a loan that brings a prohibited benefit?

"Buying and selling through credit facilities (margin) has various forms, and the ruling differs according to each. As for the difference between the buying and selling price, it is a clear benefit that is impermissible for the lender to take; because scholars have restricted any benefit gained by the lender from the borrower. Therefore, they have unanimously forbidden selling to him at a reduced price if it was stipulated, and some even if it was not stipulated. Some scholars have even disliked selling to him at all, even without a reduction. Anything of this nature that is done as a trick (legal ruse) is forbidden. Therefore, we advise staying away from such transactions."