influogames I was hoping for the spine 4.2 runtime. I'm not sure the improved mask architecture you mentioned were only intended for 4.3.
This change will not be back-ported to the 4.2 branch once it's released on 4.3-beta, sorry. As I said in the above posting, fixing it one way would introduce different memory leaks, and also risking breaking existing projects. Thus this breaking change can only be implemented in a beta branch, 4.3-beta in this case.
Meanwhile would you recommend us to not use mask interactions?
I would not avoid mask materials just because of additional Material objects allocated. It depends on your concrete project of course, on the actual memory allocation size, whether this poses a problem or not. You could then profile on the target device whether enabling and disabling mask material usage has any impact on your measured framerate, whether it actually leads to GC hickups.
