HDR merge lockups up daily

I’m a heavy volume shooter, I see daily that Lightroom Classic will fail on HDR merges. No errors, no crashes, LRC will just hang indefinitely on “Merging HDR….”. 

You can use the program normally. The only way to fix it is to terminate LRC, re-open then merge the stacks again. I notice it usually hangs on large volumes, say 30-40 stacks at a time.