@hjx1994 Very sorry for the troubles and thanks for reporting! Unfortunately the mask handling structures in the 4.2 spine-unity runtime is suboptimal, and fixing it one way would introduce different memory leaks, and also risking breaking existing projects. As a result I've reverted the last commit, sorry to say.
The good news is that we have already solved this problem via a better mask architecture already in an internal dev branch, which will be released in the current beta branch alongside with threading implementation as soon as the final cleanup is done. Unfortunately it will take a bit of time still, as porting of the 4.3-beta editor changes is yet to be completed.
