50% CPU after restart Session Restore, seamonkey.exe

0, ntoskrnl.exe!ExAcquireSharedWaitForExclusive+0x132
1, ntoskrnl.exe!ExAcquireSharedWaitForExclusive+0x171
2, ntoskrnl.exe!IoGetRequestorProcessId+0x598
3, hal.dll!HalClearSoftwareInterrupt+0x342
4, xul.dll!xpc_LocalizeContext+0x7930
5, xul.dll!DumpJSValue+0x229
6, xul.dll!xpc_LocalizeContext+0xd355
7, mozjs.dll!js::BaseProxyHandler::finalize+0x149e6
8, mozjs.dll!js::BaseProxyHandler::finalize+0xda0f
9, 0x5660060