Bugzilla

FWIW (need to look into this later), running memory measurements in about:memory in a debug build will assert after a couple reloads with the console open:
```
2022	  MOZ_ASSERT(gcTotal == rtStats.gcHeapChunkTotal);
(gdb) p gcTotal
$1 = 33554416
(gdb) p rtStats.gcHeapChunkTotal
$2 = 33554432
(gdb) bt
#0  0x00007fffe4b4f3db in xpc::ReportJSRuntimeExplicitTreeStats(JS::RuntimeStats const&, nsTSubstring<char> const&, nsIHandleReportCallback*, nsISupports*, bool, unsigned long*) (rtStats=..., rtPath=..., handleReport=0x7fff761e49e0, data=0x0, anonymize=false, rtTotalOut=0x7fffffff9230) at js/xpconnect/src/XPCJSRuntime.cpp:2022
#1  0x00007fffe4b55976 in xpc::JSReporter::CollectReports(nsBaseHashtable<nsUint64HashKey, nsTString<char>, nsTString<char>, nsDefaultConverter<nsTString<char>, nsTString<char> > >*, nsBaseHashtable<nsUint64HashKey, nsTString<char>, nsTString<char>, nsDefaultConverter<nsTString<char>, nsTString<char> > >*, nsIHandleReportCallback*, nsISupports*, bool) (windowPaths=0x7fffffffa940, topWindowPaths=0x7fffffffa918, handleReport=0x7fff761e49e0, data=0x0, anonymize=false) at js/xpconnect/src/XPCJSRuntime.cpp:2273
#2  0x00007fffe5af6698 in nsWindowMemoryReporter::CollectReports(nsIHandleReportCallback*, nsISupports*, bool) (this=0x7fffcbb66800, aHandleReport=0x7fff761e49e0, aData=0x0, aAnonymize=false) at dom/base/nsWindowMemoryReporter.cpp:576
#3  0x00007fffe30d837d in nsMemoryReporterManager::DispatchReporter(nsIMemoryReporter*, bool, nsIHandleReportCallback*, nsISupports*, bool)::$_0::operator()() const (this=0x7fffb3614668) at xpcom/base/nsMemoryReporterManager.cpp:1844
#4  0x00007fffe30d8289 in mozilla::detail::RunnableFunction<nsMemoryReporterManager::DispatchReporter(nsIMemoryReporter*, bool, nsIHandleReportCallback*, nsISupports*, bool)::$_0>::Run() (this=0x7fffb3614640) at obj-x86_64-pc-linux-gnu/dist/include/nsThreadUtils.h:534
#5  0x00007fffe326eb5a in mozilla::RunnableTask::Run() (this=0x7fffc0bed780) at xpcom/threads/TaskController.cpp:482
```

FWIW (need to look into this later), running memory measurements in about:memory in a debug build will assert (repeatably) after a couple reloads with the console open:
```
2022	  MOZ_ASSERT(gcTotal == rtStats.gcHeapChunkTotal);
(gdb) p gcTotal
$1 = 33554416
(gdb) p rtStats.gcHeapChunkTotal
$2 = 33554432
(gdb) bt
#0  0x00007fffe4b4f3db in xpc::ReportJSRuntimeExplicitTreeStats(JS::RuntimeStats const&, nsTSubstring<char> const&, nsIHandleReportCallback*, nsISupports*, bool, unsigned long*) (rtStats=..., rtPath=..., handleReport=0x7fff761e49e0, data=0x0, anonymize=false, rtTotalOut=0x7fffffff9230) at js/xpconnect/src/XPCJSRuntime.cpp:2022
#1  0x00007fffe4b55976 in xpc::JSReporter::CollectReports(nsBaseHashtable<nsUint64HashKey, nsTString<char>, nsTString<char>, nsDefaultConverter<nsTString<char>, nsTString<char> > >*, nsBaseHashtable<nsUint64HashKey, nsTString<char>, nsTString<char>, nsDefaultConverter<nsTString<char>, nsTString<char> > >*, nsIHandleReportCallback*, nsISupports*, bool) (windowPaths=0x7fffffffa940, topWindowPaths=0x7fffffffa918, handleReport=0x7fff761e49e0, data=0x0, anonymize=false) at js/xpconnect/src/XPCJSRuntime.cpp:2273
#2  0x00007fffe5af6698 in nsWindowMemoryReporter::CollectReports(nsIHandleReportCallback*, nsISupports*, bool) (this=0x7fffcbb66800, aHandleReport=0x7fff761e49e0, aData=0x0, aAnonymize=false) at dom/base/nsWindowMemoryReporter.cpp:576
#3  0x00007fffe30d837d in nsMemoryReporterManager::DispatchReporter(nsIMemoryReporter*, bool, nsIHandleReportCallback*, nsISupports*, bool)::$_0::operator()() const (this=0x7fffb3614668) at xpcom/base/nsMemoryReporterManager.cpp:1844
#4  0x00007fffe30d8289 in mozilla::detail::RunnableFunction<nsMemoryReporterManager::DispatchReporter(nsIMemoryReporter*, bool, nsIHandleReportCallback*, nsISupports*, bool)::$_0>::Run() (this=0x7fffb3614640) at obj-x86_64-pc-linux-gnu/dist/include/nsThreadUtils.h:534
#5  0x00007fffe326eb5a in mozilla::RunnableTask::Run() (this=0x7fffc0bed780) at xpcom/threads/TaskController.cpp:482
```

(Moved.)