The only thing holding the bird feeder are 3 very strong suction cups so it’s very easy to install it and remove it as long as you have access to the window.
Users that have encountered problems with the product state that the customer service is very helpful and responsive. They will even send you a replacement if the feeder has been knocked off by accident.
Since it’s a see through bird feeder and it’s attached to a window the birds are afraid to go there at first, especially if there is a lot of movement close to the window.
There are no trap doors, hinges or anything else that protects the seeds from squirrels so the only way to protect against them is to put the feeder in a way that the squirrels can’t reach the bird feeder jumping or climbing.