Specifically, double clicking/tapping on an item on the left side (ie items you can build) should add it to the queue, while double-clicking on an item on the right side should remove it. (These would be affected by the 1/10/100x multiplier buttons as well.)
Specifically, double clicking/tapping on an item on the left side (ie items you can build) should add it to the queue, while double-clicking on an item on the right side should remove it. (These would be affected by the 1/10/100x multiplier buttons as well.)