Android app keeps crashing after updating server to version 30.0.2

[mmattq]

Cause of error

Exception in thread "Syncfolder thread" java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String com.owncloud.android.datamodel.OCFile.getEtag()' on a null object reference
    at com.owncloud.android.operations.SynchronizeFolderOperation.checkForChanges(SynchronizeFolderOperation.java:172)
    at com.owncloud.android.operations.SynchronizeFolderOperation.run(SynchronizeFolderOperation.java:131)
    at com.owncloud.android.lib.common.operations.RemoteOperation.execute(RemoteOperation.java:193)
    at com.owncloud.android.services.SyncFolderHandler.doOperation(SyncFolderHandler.java:106)
    at com.owncloud.android.services.SyncFolderHandler.handleMessage(SyncFolderHandler.java:79)
    at android.os.Handler.dispatchMessage(Handler.java:111)
    at android.os.Looper.loopOnce(Looper.java:238)
    at android.os.Looper.loop(Looper.java:357)
    at android.os.HandlerThread.run(HandlerThread.java:85)

App information

• ID: com.nextcloud.client
• Version: 30300690
• Build flavor: generic

Device information

• Brand: motorola
• Device: pstar
• Model: motorola edge 20 pro
• Id: T1RAS33.55-15-10-6
• Product: pstar_retaile

Firmware

• SDK: 33
• Release: 13
• Incremental: 2b5db-18379

[joshtrichards]

Duplicate of #13784