I have noticed that Hearthstone freezes during the finding opponent animation on the Mac. I usually tab to another program during that time and when I switch back the screen doesn’t refresh, indicating that the main GUI thread is busy.
This also happens when clicking on the spectator icon which hangs until the actual spectating is started.
Is this a known issue or is there a solution for it?
Hey, fmoraes! I can’t seem to find anything that should be causing this behavior so far from my search. I’d be interested in seeing in an SMC reset might help with the behavior and if we can gather the system reports to check out some of the error and system logs.
For the system reports, could you email them over to techinfo@blizzard.com under the subject, ATTN: Caterpepi - OSX Freeze [42632] ? Once sent, respond back here and let us know if the SMC reset seemed to have helped a bit or not 
This inbox is not monitored and will not send responses. It’s used to collect information for Technical Support to assist in troubleshooting.
I’ve sent the system report as requested.
Update: I also did the SMC reset today and no change. The hang persists, even when playing a solo adventure.
I took a sample of the Hearthstone process at the time of the hang and this is what’s going on in the main thread:
2368 Thread_1492337 DispatchQueue_1: com.apple.main-thread (serial)
+ 2368 ??? (in <unknown binary>) [0x13cd74ca6]
+ 2368 ves_icall_System_Net_Dns_GetHostByAddr_internal (in libmonobdwgc-2.0.dylib) + 308 [0x108c65422]
+ 2368 getnameinfo (in libsystem_info.dylib) + 172 [0x7fff675ea66c]
+ 2368 _getnameinfo_interface_internal (in libsystem_info.dylib) + 212 [0x7fff675ea754]
+ 2368 si_nameinfo (in libsystem_info.dylib) + 1306 [0x7fff675eae5a]
+ 2368 si_host_byaddr (in libsystem_info.dylib) + 122 [0x7fff675f47aa]
+ 2368 search_host_byaddr (in libsystem_info.dylib) + 249 [0x7fff675f48b9]
+ 2368 si_host_byaddr (in libsystem_info.dylib) + 122 [0x7fff675f47aa]
+ 2368 mdns_hostbyaddr (in libsystem_info.dylib) + 868 [0x7fff675f4d44]
+ 2368 _mdns_search_ex (in libsystem_info.dylib) + 2074 [0x7fff675ee4da]
+ 2368 kevent (in libsystem_kernel.dylib) + 10 [0x7fff6762f766]
I was not able to reply above, so here it is from my secondary account:
Given the above, I was able to capture the query hanging via packet capture and try it from command line which also hangs. So, I tested changing the DNS server I am using and the problem is gone. So, this is a work around but the fact is that Hearthstone shouldn’t be doing a blocking network operation in the main thread as shown above as it will hang the client.