Crash When Notarize without Internet Access

APP crashes when notarizing without Internet access (WiFi or LTE). The following is the error message.

2019-09-02 12:56:58.411 7352-7677/org.witness.proofmode E/AndroidRuntime: FATAL EXCEPTION: Thread-3
    Process: org.witness.proofmode, PID: 7352
    java.lang.NullPointerException: Attempt to read from null array
        at com.eternitywall.ots.StreamDeserializationContext.readVaruint(StreamDeserializationContext.java:58)
        at com.eternitywall.ots.StreamDeserializationContext.readVarbytes(StreamDeserializationContext.java:79)
        at com.eternitywall.ots.StreamDeserializationContext.readVarbytes(StreamDeserializationContext.java:75)
        at com.eternitywall.ots.attestation.TimeAttestation.deserialize(TimeAttestation.java:47)
        at com.eternitywall.ots.Timestamp.doTagOrAttestation(Timestamp.java:74)
        at com.eternitywall.ots.Timestamp.deserialize(Timestamp.java:67)
        at com.eternitywall.ots.Timestamp.doTagOrAttestation(Timestamp.java:81)
        at com.eternitywall.ots.Timestamp.deserialize(Timestamp.java:67)
        at com.eternitywall.ots.Timestamp.doTagOrAttestation(Timestamp.java:81)
        at com.eternitywall.ots.Timestamp.deserialize(Timestamp.java:67)
        at com.eternitywall.ots.DetachedTimestampFile.deserialize(DetachedTimestampFile.java:91)
        at com.eternitywall.ots.OpenTimestamps.info(OpenTimestamps.java:52)
        at org.witness.proofmode.notarization.OpenTimestampsNotarizationProvider.notarize(OpenTimestampsNotarizationProvider.java:22)
        at org.witness.proofmode.service.MediaWatcher.handleIntent(MediaWatcher.java:169)
        at org.witness.proofmode.service.MediaWatcher$1.run(MediaWatcher.java:64)

Environment

Android API 26
Device WiFi and LTE are disabled but GPS sensor is enabled
Preferences autoNotarize is enabled but trackLocation, trackDeviceId and trackMobileNetwork are disabled

guardianproject / proofmode-android

Crash When Notarize without Internet Access #64

Environment