Quick answer: Without the Weekend Holding add-on, open positions close automatically at 20:30 UTC before the weekend, and you can't trade markets that stay open, such as crypto. With it, positions may be held through the weekend.
Without the add-on
All open positions are closed automatically at 20:30 UTC ahead of the weekend
Positions cannot be carried into the next week
Weekend-open markets, such as crypto, can't be traded
With the add-on
Positions may remain open over the weekend
Weekend-open markets can be traded
What it doesn't do
It doesn't guarantee execution price, protect against weekend gaps, or change any news rule — weekend holding and news are separate conditions. Gap risk on Sunday open is yours, and your drawdown limits apply to wherever equity lands.
My trade closed on Friday despite the add-on. Check it's attached to the correct account; support will also check whether the instrument was closing, whether another rule triggered the closure, and the account status.
See also: Traderscale Add-Ons Overview · Why Was My Trade Closed Automatically?