Guild Wars 2

From the latest patch notes:
One armor, strength, speed, or rejuvenation booster can be converted to an Enchanted Combat Booster. This booster allows the player to choose from an armor, strength, speed, or rejuvenation buff.
One experience, gathering, crafting, or magic find booster (or two karma boosters) can be converted to an Enchanted Reward Booster. This booster allows the player to choose from an experience, gathering, crafting, magic find, or karma buff.

I have no idea how to convert my boosters though. Since clicking on them just causes me to use them.

Apparently this thread over in the BLTC forum goes into a good and detailed explanation of how the powder and all that works (with pics).

It seems that activating a single powder will convert a single booster that is currently in your inventory into the appropriate Enchanted Booster type. So make sure you have any boosters out of your inventory that you want to keep in their current form when you use the powder to prevent them from being converted.

I read it wrong and one powder converts only one booster, apparently. I’ll need over a hundred powders to convert my boosters over to the Enchanted Booster items. Not going to happen, especially at 125 gems per powder (cost of a key) or even 20-30 minutes per key run for one powder from a chest with a free key.

edit
Tweaked wording for more accurate (and saddening) information.

Do the new Boost Enchantment Powders function in a way that is similar to the old transmutation windows?

Perhaps activating the powder opens a window where you have to place a booster into it to convert it into a generic, stackable booster. I have no plans to purchase any so I will only find out after getting one from a BL Chest after my next key run. I also do not plan to ever convert my karma boosters to powders as it seems to only be a way to lessen the number of karma boosters out there. I can use two karma boosters, or turn those two into a single generic booster that is good for a single karma booster use. Makes no sense outside of a way for them to make people freely destroy half of their karma boosters.

Activating a powder converts boosters in your inventory into a special booster. This special booster lets you choose out of a few options, then immediately use it upon confirmation. Using the powder only converts into one booster, some of them require 2 boosters to exchange into the special booster.

It’s one booster per powder

It only converts one regular booster (not a karma booster, that requires 2 of these) to an enchanted booster.

I’ve gotten one of them. I dragged all my boosters into inventory to see what would happen. When I activated the powder it converted one of the regular boosters to one enchanted booster.

One thing I’ve noticed about ANet, they have a positive genius for poorly written, confusing instructions/explanations.