Widows reporting ff crash after normal shutdown?

Question

Minor exit problem, but now 2-3x in about one week.
About:crashes may show last weeks, but NOT today.
Nothing recent has brought up Moz crash reporter.
Noticed same xul.dll report, last week and today.
Below is from WINDOWS crash report today.
Problem signature:
Problem Event Name: APPCRASH
Application Name: firefox.exe
Application Version: 19.0.2.4814
Application Timestamp: 5138a1d3
Fault Module Name: xul.dll
Fault Module Version: 19.0.2.4814
Fault Module Timestamp: 5138a0ed
Exception Code: c0000005
Exception Offset: 00172818
OS Version: 6.1.7601.2.1.0.768.3
Locale ID: 1033
Additional Information 1: a7aa
Additional Information 2: a7aa91f17ea749d42a4de3b390fa5b3d
Additional Information 3: a7aa
Additional Information 4: a7aa91f17ea749d42a4de3b390fa5b3d
Again, just a minor exit problem report, after an otherwise normal exit.

Answer 1

New but very similar crash info from today...
Still from the most used profile, but will now lean more to the other two (per the suggested profiles experiment). Still had been on facebook earlier, but was nowhere near there on exit today. Think the last tab closed today was either slate or wikipedia.
Still no Moz crash reporting window, at least not in any recent weeks. Still not shown in about:crashes, but last entries are twice on 2013.03.03, and once on 2013.01.06 before that. Unknown if directly related, but 3.3 could have been the known incident(s) from last week, when it did not yet seem to be any reoccurring issue. They cannot now be converted to bp-numbers due to "throttling," nor the two from this week because theses latest ones definitely don't even show up at all in about:crashes.
Again, all known incidents had no Moz crash window, just the Windows crash menu. Each time was immediately after an otherwise normal and intentional shutdown, and xul.dll was always reported as the fault module.
Problem signature:
Problem Event Name: APPCRASH
Application Name: firefox.exe
Application Version: 19.0.2.4814
Application Timestamp: 5138a1d3
Fault Module Name: xul.dll
Fault Module Version: 19.0.2.4814
Fault Module Timestamp: 5138a0ed
Exception Code: c0000005
Exception Offset: 00172818
OS Version: 6.1.7601.2.1.0.768.3
Locale ID: 1033
Additional Information 1: a7aa
Additional Information 2: a7aa91f17ea749d42a4de3b390fa5b3d
Additional Information 3: a7aa
Additional Information 4: a7aa91f17ea749d42a4de3b390fa5b3d