For this product we wanted to capture the “+” key for when users wanted to Add something to their console. The confusion for me came from the fact the the “+” is used in the key() method for joining sequences of keys to get multi-key dispatching (e.g. pressing Control and Return at the same time).
An unfortunate by-product of the above, however, is that the same function will fire if the user hits just the “=” key. A pretty trivial trade-off IMHO. If anyone can think of a way to differentiate between the two let me know!