Thanks for your response. It makes me feel the post in the forum does serve with some actions.
I surely understand this bug must be caused by an unintentional error and it is very normal in software developement. The reason I feel dissatisified is this bug should be thought as a major bug and fixed in maintanence revision such as 8.2.1, but it is postponed to 8.5.1, which is the maintanence release of another major paid version.
I also hope the ironic way to express my complaint does not hurt your feeling.