Not sure if this extends country wide or is targeted, but I stumbled across a 50% Off Hungry Jacks with over $20 spend on Deliveroo. (Does not include delivery price)
No Coupon needed, but the 50% display offer will show on the store and automatically when adding $20 worth of food to the cart.
Edit: based on comments.
50% off orders of $20 or more from Hungry Jacks between 17.5.2021 and 23.5.2021. This offer may be extended or withdrawn without notice. Discount displayed at check out. Geographical restrictions and delivery fees apply.