zero slur at tick 95040(95040) track 0 in measure 33-33 tick 95040 ticks 0

When I play the attached score in the newly compiled dev MuseScore, I get a curious debug message.
zero slur at tick 95040(95040) track 0 in measure 33-33 tick 95040 ticks 0

The playback halts for 2 or 3 seconds, and all the notes are sustained, then it continues in a slower tempo.

Here is an image of measure 33, but doesn't have a slur, neither do I find a slur in the xml file at measure 33.

I also get a lot of other debug message. I have no idea if they are related. But here they are in case it is helpful to someone.

/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: ATTACK (1) 353
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: HOLD (2) 26465
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: DECAY (3) 1279212
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: SUSTAIN (4) -1
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: RELEASE (5) 26466
/Users/jnewton/OpenSource/MuseScore/libmscore/layout.cpp:Ms::Score::doLayout:
/Users/jnewton/OpenSource/MuseScore/libmscore/slur.cpp:Ms::Slur::computeBezier: zero slur at tick 95040(95040) track 0 in measure 33-33 tick 95040 ticks 0
/Users/jnewton/OpenSource/MuseScore/libmscore/layout.cpp:Ms::Score::doLayout:
/Users/jnewton/OpenSource/MuseScore/libmscore/slur.cpp:Ms::Slur::computeBezier: zero slur at tick 95040(95040) track 0 in measure 33-33 tick 95040 ticks 0
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: DELAY (0) 43
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: ATTACK (1) 353
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: HOLD (2) 88200
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: DECAY (3) 661397
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: SUSTAIN (4) -1
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: RELEASE (5) 26466
/Users/jnewton/OpenSource/MuseScore/libmscore/layout.cpp:Ms::Score::doLayoutRange: 10080-10080
/Users/jnewton/OpenSource/MuseScore/libmscore/layout.cpp:Ms::Score::doLayoutRange: 10080-10080
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: DELAY (0) 43
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: ATTACK (1) 353
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: HOLD (2) 26465
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: DECAY (3) 1102737
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: SUSTAIN (4) -1
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: RELEASE (5) 26466
/Users/jnewton/OpenSource/MuseScore/libmscore/layout.cpp:Ms::Score::doLayoutRange: 10200-10200
/Users/jnewton/OpenSource/MuseScore/libmscore/layout.cpp:Ms::Score::doLayoutRange: 10200-10200
/Users/jnewton/OpenSource/MuseScore/libmscore/layout.cpp:Ms::Score::doLayout:
/Users/jnewton/OpenSource/MuseScore/libmscore/slur.cpp:Ms::Slur::computeBezier: zero slur at tick 95040(95040) track 0 in measure 33-33 tick 95040 ticks 0
/Users/jnewton/OpenSource/MuseScore/libmscore/slur.cpp:Ms::Slur::write: broken slur not written
/Users/jnewton/OpenSource/MuseScore/libmscore/slur.cpp:Ms::Slur::write: broken slur not written
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: DELAY (0) 43
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: ATTACK (1) 353
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: HOLD (2) 61757
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: DECAY (3) 705600
/Users/jnewton/OpenSource/MuseScore/fluid/voice.cpp:FluidS::Voice::voice_start: SUSTAIN (4) -1