Crash on dialog when trying to delete 16000 files

Press "delete" witg 16000 files selected, the list is unscrollable, and the activity crashes:

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android.view.WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@2b08861 is not valid; is your activity running?
 at android.view.ViewRootImpl.setView(ViewRootImpl.java:748)
 at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:343)
 at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:94)
 at android.widget.Toast$TN.handleShow(Toast.java:504)
 at android.widget.Toast$TN$2.handleMessage(Toast.java:384)
 at android.os.Handler.dispatchMessage(Handler.java:102)
 at android.os.Looper.loop(Looper.java:154)
 at android.app.ActivityThread.main(ActivityThread.java:6351)
 at java.lang.reflect.Method.invoke(Native Method)
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:896)
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:786)
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Start by reproducing deletion with about 16,000 selected files and trace the Android stack trace through the delete dialog and Toast handling. Done means the selected-file list remains usable and the activity does not crash when the deletion dialog is opened.