diff --git a/music21/stream/base.py b/music21/stream/base.py
index b2d0a7b27..1d41834f0 100644
--- a/music21/stream/base.py
+++ b/music21/stream/base.py
@@ -6480,7 +6480,7 @@ class Stream(core.StreamCoreMixin, base.Music21Object):
         '''
         This method calls a sequence of Stream methods on this Stream to prepare
         notation, including creating voices for overlapped regions, Measures
-        if necessary, creating ties, beams, and accidentals.
+        if necessary, creating ties, beams, accidentals, and tuplet brackets.
 
         If `inPlace` is True, this is done in-place;
         if `inPlace` is False, this returns a modified deep copy.
@@ -12964,7 +12964,7 @@ class Part(Stream):
         alteredPitches=None,
         cautionaryPitchClass=True,
         cautionaryAll=False,
-        inPlace=True,
+        inPlace=False,
         overrideStatus=False,
         cautionaryNotImmediateRepeat=True,
         tiePitchSet=None,
@@ -12974,7 +12974,7 @@ class Part(Stream):
         provides the management of passing pitches from
         a past Measure to each new measure for processing.
 
-        TODO: by default inPlace should be False
+        Changed in v.7 -- `inPlace` defaults False
         '''
         if not inPlace:  # make a copy
             returnObj = self.coreCopyAsDerivation('makeAccidentals')
diff --git a/music21/stream/makeNotation.py b/music21/stream/makeNotation.py
index 87456fffc..da1a92f47 100644
--- a/music21/stream/makeNotation.py
+++ b/music21/stream/makeNotation.py
@@ -610,6 +610,7 @@ def makeMeasures(
         if not match:
             if start == end == oMax:
                 post.storeAtEnd(e)
+                continue
             else:
                 raise stream.StreamException(
                     f'cannot place element {e} with start/end {start}/{end} within any measures')

diff --git a/music21/stream/tests.py b/music21/stream/tests.py
index 4817fff3c..96bc530e7 100644
--- a/music21/stream/tests.py
+++ b/music21/stream/tests.py
@@ -2044,7 +2044,7 @@ class Test(unittest.TestCase):
         obj = expressions.TextExpression('FREEZE')
         s.insert(3, obj)
         s.makeMeasures(inPlace=True)
-        self.assertEqual(len(s.measure(1).getElementsByClass('Expression')), 1)
+        self.assertEqual(len(s.flat.getElementsByClass('Expression')), 1)
 
     def testRemove(self):
         '''Test removing components from a Stream.

Durationless element can get inserted twice; missing safeguard in coreGuardBeforeAddElement
**music21 version**

7


**Problem summary**
`makeMeasures` can insert the same element in a stream twice when the element coincides with the end of the stream. We made this change in #592 but didn't notice that it was inserting the identical element from the flat source into the newly created measure.


**Steps to reproduce**

```
>>> p = stream.Part()
>>> p.insert(4, meter.TimeSignature())
>>> p.makeMeasures(inPlace=True)
>>> for el in p.recurse():
...   print(el, id(el))
```

**Expected vs. actual behavior**
<music21.stream.Measure 1 offset=0.0> 4465547536
<music21.clef.TrebleClef> 4465548496
<music21.meter.TimeSignature 4/4> 4465547392
<music21.meter.TimeSignature 4/4> **4465410544**
<music21.bar.Barline type=final> 4465692736
<music21.meter.TimeSignature 4/4> **4465410544**

**More information**
This came up putting together the make measures patch for MIDI import, since the conductor track will only extend as far as the last element (which will be durationless time signature or key signature), and if we make measures, we choke here.

Making a deep copy before inserting might work, but in addition, I would think a safeguard is missing here? It wasn't obvious to me since `storeAtEnd` runs `coreGuardBeforeAddElement`.
music21/stream/tests.py::Test::testMakeMeasuresLastElementNoDuration
music21/stream/tests.py::Test::testAccumulatedTimeA music21/stream/tests.py::Test::testAccumulatedTimeB music21/stream/tests.py::Test::testActivateVariantsA music21/stream/tests.py::Test::testActivateVariantsB music21/stream/tests.py::Test::testActivateVariantsBySpanA music21/stream/tests.py::Test::testActivateVariantsBySpanB music21/stream/tests.py::Test::testActivateVariantsC music21/stream/tests.py::Test::testActivateVariantsD music21/stream/tests.py::Test::testActivateVariantsE music21/stream/tests.py::Test::testActiveSiteCopiedStreams music21/stream/tests.py::Test::testActiveSiteMangling music21/stream/tests.py::Test::testActiveSites music21/stream/tests.py::Test::testActiveSitesMultiple music21/stream/tests.py::Test::testAddSlurByMelisma music21/stream/tests.py::Test::testAnalyze music21/stream/tests.py::Test::testAppendFails music21/stream/tests.py::Test::testAugmentOrDiminishBasic music21/stream/tests.py::Test::testAugmentOrDiminishCorpus music21/stream/tests.py::Test::testAugmentOrDiminishHighestTimes music21/stream/tests.py::Test::testBestTimeSignature music21/stream/tests.py::Test::testChordifyA music21/stream/tests.py::Test::testChordifyB music21/stream/tests.py::Test::testChordifyC music21/stream/tests.py::Test::testChordifyD music21/stream/tests.py::Test::testChordifyE music21/stream/tests.py::Test::testChordifyF music21/stream/tests.py::Test::testChordifyG music21/stream/tests.py::Test::testChordifyImported music21/stream/tests.py::Test::testChordifyRests music21/stream/tests.py::Test::testChordifyTagPartA music21/stream/tests.py::Test::testChordifyTagPartB music21/stream/tests.py::Test::testClefs music21/stream/tests.py::Test::testContainerHierarchyA music21/stream/tests.py::Test::testContextNestedA music21/stream/tests.py::Test::testContextNestedB music21/stream/tests.py::Test::testContextNestedC music21/stream/tests.py::Test::testContextNestedD music21/stream/tests.py::Test::testDeepcopyActiveSite music21/stream/tests.py::Test::testDeepcopySpanners music21/stream/tests.py::Test::testDerivationA music21/stream/tests.py::Test::testDerivationB music21/stream/tests.py::Test::testDerivationC music21/stream/tests.py::Test::testDerivationMethodA music21/stream/tests.py::Test::testDoubleStreamPlacement music21/stream/tests.py::Test::testElements music21/stream/tests.py::Test::testElementsHighestTimeA music21/stream/tests.py::Test::testElementsHighestTimeB music21/stream/tests.py::Test::testElementsHighestTimeC music21/stream/tests.py::Test::testExtendDurationA music21/stream/tests.py::Test::testExtendTiesA music21/stream/tests.py::Test::testExtendTiesB music21/stream/tests.py::Test::testExtractedNoteAssignLyric music21/stream/tests.py::Test::testFinalBarlinePropertyA music21/stream/tests.py::Test::testFinalBarlinePropertyB music21/stream/tests.py::Test::testFindConsecutiveNotes music21/stream/tests.py::Test::testFindGaps music21/stream/tests.py::Test::testFlatCachingA music21/stream/tests.py::Test::testFlatCachingB music21/stream/tests.py::Test::testFlatCachingC music21/stream/tests.py::Test::testFlatSimple music21/stream/tests.py::Test::testFlattenUnnecessaryVoicesA music21/stream/tests.py::Test::testGetElementAfterElement music21/stream/tests.py::Test::testGetElementAtOrBeforeBarline music21/stream/tests.py::Test::testGetElementBeforeOffsetA music21/stream/tests.py::Test::testGetElementBeforeOffsetB music21/stream/tests.py::Test::testGetElementsByContextStream music21/stream/tests.py::Test::testGetElementsByOffsetZeroLength music21/stream/tests.py::Test::testGetInstrumentFromMxl music21/stream/tests.py::Test::testGetInstrumentManual music21/stream/tests.py::Test::testGetKeySignatures music21/stream/tests.py::Test::testGetKeySignaturesThreeMeasures music21/stream/tests.py::Test::testGetTimeSignatures music21/stream/tests.py::Test::testGetVariantsA music21/stream/tests.py::Test::testGraceChords music21/stream/tests.py::Test::testGracesInStream music21/stream/tests.py::Test::testHaveAccidentalsBeenMadeA music21/stream/tests.py::Test::testHaveAccidentalsBeenMadeB music21/stream/tests.py::Test::testHaveAccidentalsBeenMadeInVoices music21/stream/tests.py::Test::testHaveBeamsBeenMadeA music21/stream/tests.py::Test::testHaveBeamsBeenMadeB music21/stream/tests.py::Test::testInsertAndShiftBasic music21/stream/tests.py::Test::testInsertAndShiftMultipleElements music21/stream/tests.py::Test::testInsertAndShiftNoDuration music21/stream/tests.py::Test::testInsertIntoNoteOrChordA music21/stream/tests.py::Test::testInsertIntoNoteOrChordB music21/stream/tests.py::Test::testInvertDiatonicA music21/stream/tests.py::Test::testInvertDiatonicQuickSearch music21/stream/tests.py::Test::testIsFlat music21/stream/tests.py::Test::testIteration music21/stream/tests.py::Test::testMakeAccidentalsA music21/stream/tests.py::Test::testMakeAccidentalsB music21/stream/tests.py::Test::testMakeAccidentalsC music21/stream/tests.py::Test::testMakeAccidentalsD music21/stream/tests.py::Test::testMakeAccidentalsOctaveKS music21/stream/tests.py::Test::testMakeAccidentalsTies music21/stream/tests.py::Test::testMakeAccidentalsWithKeysInMeasures music21/stream/tests.py::Test::testMakeChordsBuiltA music21/stream/tests.py::Test::testMakeChordsBuiltB music21/stream/tests.py::Test::testMakeChordsBuiltC music21/stream/tests.py::Test::testMakeChordsBuiltD music21/stream/tests.py::Test::testMakeChordsImported music21/stream/tests.py::Test::testMakeMeasuresInPlace music21/stream/tests.py::Test::testMakeMeasuresMeterStream music21/stream/tests.py::Test::testMakeMeasuresTimeSignatures music21/stream/tests.py::Test::testMakeMeasuresWithBarlines music21/stream/tests.py::Test::testMakeNotationA music21/stream/tests.py::Test::testMakeNotationB music21/stream/tests.py::Test::testMakeNotationByMeasuresA music21/stream/tests.py::Test::testMakeNotationByMeasuresB music21/stream/tests.py::Test::testMakeNotationC music21/stream/tests.py::Test::testMakeNotationKeySignatureMultiVoice music21/stream/tests.py::Test::testMakeNotationKeySignatureOneVoice music21/stream/tests.py::Test::testMakeNotationScoreA music21/stream/tests.py::Test::testMakeNotationScoreB music21/stream/tests.py::Test::testMakeNotationScoreC music21/stream/tests.py::Test::testMakeRestsA music21/stream/tests.py::Test::testMakeRestsB music21/stream/tests.py::Test::testMakeTies music21/stream/tests.py::Test::testMakeTupletBracketsA music21/stream/tests.py::Test::testMakeTupletBracketsB music21/stream/tests.py::Test::testMakeVoicesA music21/stream/tests.py::Test::testMakeVoicesB music21/stream/tests.py::Test::testMeasureAndTieCreation music21/stream/tests.py::Test::testMeasureBarDurationProportion music21/stream/tests.py::Test::testMeasureBarline music21/stream/tests.py::Test::testMeasureGrouping music21/stream/tests.py::Test::testMeasureLayout music21/stream/tests.py::Test::testMeasureOffsetMap music21/stream/tests.py::Test::testMeasureOffsetMapPostTie music21/stream/tests.py::Test::testMeasureRange music21/stream/tests.py::Test::testMeasureStream music21/stream/tests.py::Test::testMeasuresA music21/stream/tests.py::Test::testMeasuresAndMakeMeasures music21/stream/tests.py::Test::testMeasuresB music21/stream/tests.py::Test::testMeasuresC music21/stream/tests.py::Test::testMeasuresSuffix music21/stream/tests.py::Test::testMelodicIntervals music21/stream/tests.py::Test::testMelodicIntervalsB music21/stream/tests.py::Test::testMergeElements music21/stream/tests.py::Test::testMetadataOnStream music21/stream/tests.py::Test::testMidiEventsBuilt music21/stream/tests.py::Test::testMultipartStream music21/stream/tests.py::Test::testMusicXMLGenerationViaPropertyA music21/stream/tests.py::Test::testMusicXMLGenerationViaPropertyB music21/stream/tests.py::Test::testMusicXMLGenerationViaPropertyC music21/stream/tests.py::Test::testOpusSearch music21/stream/tests.py::Test::testOpusWrite music21/stream/tests.py::Test::testOverlapsA music21/stream/tests.py::Test::testOverlapsB music21/stream/tests.py::Test::testPartDurationA music21/stream/tests.py::Test::testPartDurationB music21/stream/tests.py::Test::testPartsToVoicesA music21/stream/tests.py::Test::testPartsToVoicesB music21/stream/tests.py::Test::testQuantize music21/stream/tests.py::Test::testQuantizeMinimumDuration music21/stream/tests.py::Test::testRecurseA music21/stream/tests.py::Test::testRecurseB music21/stream/tests.py::Test::testRemove music21/stream/tests.py::Test::testRemoveByClass music21/stream/tests.py::Test::testReplace music21/stream/tests.py::Test::testReplaceA1 music21/stream/tests.py::Test::testReplaceB music21/stream/tests.py::Test::testReplaceDerived music21/stream/tests.py::Test::testScaleDurationsBasic music21/stream/tests.py::Test::testScaleOffsetsBasic music21/stream/tests.py::Test::testScaleOffsetsBasicInPlaceA music21/stream/tests.py::Test::testScaleOffsetsBasicInPlaceB music21/stream/tests.py::Test::testScaleOffsetsBasicInPlaceC music21/stream/tests.py::Test::testScaleOffsetsBasicInPlaceD music21/stream/tests.py::Test::testScaleOffsetsNested music21/stream/tests.py::Test::testScoreShowA music21/stream/tests.py::Test::testSecondsMapA music21/stream/tests.py::Test::testSecondsMapB music21/stream/tests.py::Test::testSecondsPropertyA music21/stream/tests.py::Test::testSecondsPropertyB music21/stream/tests.py::Test::testSecondsPropertyC music21/stream/tests.py::Test::testSemiFlatCachingA music21/stream/tests.py::Test::testSetElements music21/stream/tests.py::Test::testSetElementsFromOtherStreamWithEndElements music21/stream/tests.py::Test::testSimpleRecurse music21/stream/tests.py::Test::testSliceAtOffsetsBuilt music21/stream/tests.py::Test::testSliceAtOffsetsImported music21/stream/tests.py::Test::testSliceAtOffsetsSimple music21/stream/tests.py::Test::testSliceByBeatBuilt music21/stream/tests.py::Test::testSliceByBeatImported music21/stream/tests.py::Test::testSliceByGreatestDivisorBuilt music21/stream/tests.py::Test::testSliceByGreatestDivisorImported music21/stream/tests.py::Test::testSliceByQuarterLengthsBuilt music21/stream/tests.py::Test::testSliceByQuarterLengthsImported music21/stream/tests.py::Test::testSort music21/stream/tests.py::Test::testSortAndAutoSort music21/stream/tests.py::Test::testSortingAfterInsertA music21/stream/tests.py::Test::testSpannerTransferA music21/stream/tests.py::Test::testSplitAtQuarterLengthA music21/stream/tests.py::Test::testSplitAtQuarterLengthB music21/stream/tests.py::Test::testSplitAtQuarterLengthC music21/stream/tests.py::Test::testStoreAtEndFailures music21/stream/tests.py::Test::testStreamCopy music21/stream/tests.py::Test::testStreamDuration music21/stream/tests.py::Test::testStreamElementsComparison music21/stream/tests.py::Test::testStreamExceptionsOnAssert music21/stream/tests.py::Test::testStreamRecursion music21/stream/tests.py::Test::testStreamSortRecursion music21/stream/tests.py::Test::testStripTiesBuiltA music21/stream/tests.py::Test::testStripTiesBuiltB music21/stream/tests.py::Test::testStripTiesChordMembersAllTied music21/stream/tests.py::Test::testStripTiesChordMembersSomeTied music21/stream/tests.py::Test::testStripTiesChords music21/stream/tests.py::Test::testStripTiesConsecutiveInVoiceNotContainer music21/stream/tests.py::Test::testStripTiesImportedA music21/stream/tests.py::Test::testStripTiesImportedB music21/stream/tests.py::Test::testStripTiesNonMeasureContainers music21/stream/tests.py::Test::testStripTiesReplaceSpannedElements music21/stream/tests.py::Test::testStripTiesScore music21/stream/tests.py::Test::testTemplateAll music21/stream/tests.py::Test::testTransposeByPitchA music21/stream/tests.py::Test::testTransposeByPitchB music21/stream/tests.py::Test::testTransposeScore music21/stream/tests.py::Test::testTwoStreamMethods music21/stream/tests.py::Test::testTwoZeroOffset music21/stream/tests.py::Test::testVoicesA music21/stream/tests.py::Test::testVoicesALonger music21/stream/tests.py::Test::testVoicesB music21/stream/tests.py::Test::testVoicesC music21/stream/tests.py::Test::testVoicesToPartsA music21/stream/tests.py::Test::testVoicesToPartsNonNoteElementPropagation music21/stream/tests.py::Test::testYieldContainers music21/stream/tests.py::Test::test_makeBeams__1_e__after_16th_note music21/stream/tests.py::Test::test_makeBeams__1_e_n_a music21/stream/tests.py::Test::test_makeBeams__all_eighths music21/stream/tests.py::Test::test_makeBeams__all_quarters music21/stream/tests.py::Test::test_makeBeams__eighth_rests_and_eighth music21/stream/tests.py::Test::test_makeBeams__paddingLeft_2_2 music21/stream/tests.py::Test::test_makeBeams__repeated_1_e_a