Cesseilia asks you to make a potion
You have the option of asking Cesseilia to remove ingredients.
Cesseilia will only remove the last ingredient added.
I have attempted to get Cesseilia to remove earlier ingredients, by adding more of the ingredient I do not want (but which is not the last on the stack). She removes it. But, there are still too many ingredients. After 2 are removed, the potion disappears, and I cannot ask her to remove any more.
I have attempted dropping the potion, which the game tells me will let me start the potion over from scratch. When I start over, the unwanted ingredients are already in the potion.
Lvl 80 Mesmer, on Vabbi