I just came across this exception. I am afraid I cannot duplicate it but I was not interacting with an SfAutocomplete control directly, neither did I change any of the lists that are bound to it. I am using 16.2.0.41
Here is the stack trace.
07-19 15:11:19.806 I/MonoDroid(21263): System.ArgumentException: Destination array was not long enough. Check destIndex and length, and the array's lower bounds
07-19 15:11:19.806 I/MonoDroid(21263): at System.Array.Copy (System.Array sourceArray, System.Int32 sourceIndex, System.Array destinationArray, System.Int32 destinationIndex, System.Int32 length) [0x000da] in <f32579baafc1404fa37ba3ec1abdc0bd>:0
07-19 15:11:19.806 I/MonoDroid(21263): at System.Collections.Generic.List`1[T].CopyTo (T[] array, System.Int32 arrayIndex) [0x00000] in <f32579baafc1404fa37ba3ec1abdc0bd>:0
07-19 15:11:19.806 I/MonoDroid(21263): at System.Collections.Generic.List`1[T].InsertRange (System.Int32 index, System.Collections.Generic.IEnumerable`1[T] collection) [0x000aa] in <f32579baafc1404fa37ba3ec1abdc0bd>:0
07-19 15:11:19.806 I/MonoDroid(21263): at System.Collections.Generic.List`1[T].AddRange (System.Collections.Generic.IEnumerable`1[T] collection) [0x00000] in <f32579baafc1404fa37ba3ec1abdc0bd>:0
07-19 15:11:19.806 I/MonoDroid(21263): at Com.Syncfusion.Autocomplete.SfAutoComplete.GetSelectedData (System.String compareText, System.Boolean selected) [0x00015] in <9e2539381fed490cb639522ebce9405c>:0
07-19 15:11:19.806 I/MonoDroid(21263): at Com.Syncfusion.Autocomplete.SfAutoComplete.SelectedListData (System.Collections.Generic.IEnumerable`1[T] dataItems) [0x00164] in <9e2539381fed490cb639522ebce9405c>:0
07-19 15:11:19.806 I/MonoDroid(21263): at Com.Syncfusion.Autocomplete.SfAutoComplete.SelectedItemMethod () [0x0008d] in <9e2539381fed490cb639522ebce9405c>:0
07-19 15:11:19.806 I/MonoDroid(21263): at Com.Syncfusion.Autocomplete.SfAutoComplete.set_SelectedItem (System.Object value) [0x00045] in <9e2539381fed490cb639522ebce9405c>:0
07-19 15:11:19.806 I/MonoDroid(21263): at Syncfusion.SfAutoComplete.XForms.Droid.SfAutoCompleteMapping.OnAutoCompletePropertiesChanged (System.String propertyName, Syncfusion.SfAutoComplete.XForms.SfAutoComplete formsAutoComplete, Com.Syncfusion.Autocomplete.SfAutoComplete nativeAutoComplete) [0x00b90] in <84d487a0d7054ca9b6ed63d98aa6792e>:0
07-19 15:11:19.806 I/MonoDroid(21263): at Syncfusion.SfAutoComplete.XForms.Droid.SfAutoCompleteRenderer.OnElementPropertyChanged (System.Object sender, System.ComponentModel.PropertyChangedEventArgs e) [0x00013] in <84d487a0d7054ca9b6ed63d98aa6792e>:0
07-19 15:11:19.806 I/MonoDroid(21263): at (wrapper delegate-invoke) <Module>.invoke_void_object_PropertyChangedEventArgs(object,System.ComponentModel.PropertyChangedEventArgs)
07-19 15:11:19.806 I/MonoDroid(21263): at Xamarin.Forms.BindableObject.OnPropertyChanged (System.String propertyName) [0x0000a] in D:\agent_work\1\s\Xamarin.Forms.Core\BindableObject.cs:146
07-19 15:11:19.806 I/MonoDroid(21263): at Xamarin.Forms.Element.OnPropertyChanged (System.String propertyName) [0x00000] in D:\agent_work\1\s\Xamarin.Forms.Core\Element.cs:401
07-19 15:11:19.807 I/MonoDroid(21263): at Xamarin.Forms.BindableObject.SetValueActual (Xamarin.Forms.BindableProperty property, Xamarin.Forms.BindableObject+BindablePropertyContext context, System.Object value, System.Boolean currentlyApplying, Xamarin.Forms.Internals.SetValueFlags attributes, System.Boolean silent) [0x00107] in D:\agent_work\1\s\Xamarin.Forms.Core\BindableObject.cs:602
07-19 15:11:19.807 I/MonoDroid(21263): at Xamarin.Forms.BindableObject.SetValueCore (Xamarin.Forms.BindableProperty property, System.Object value, Xamarin.Forms.Internals.SetValueFlags attributes, Xamarin.Forms.BindableObject+SetValuePrivateFlags privateAttributes) [0x0015b] in D:\agent_work\1\s\Xamarin.Forms.Core\BindableObject.cs:399
07-19 15:11:19.807 I/MonoDroid(21263): at Xamarin.Forms.BindingExpression.ApplyCore (System.Object sourceObject, Xamarin.Forms.BindableObject target, Xamarin.Forms.BindableProperty property, System.Boolean fromTarget) [0x001f9] in D:\agent_work\1\s\Xamarin.Forms.Core\BindingExpression.cs:174
07-19 15:11:19.807 I/MonoDroid(21263): at Xamarin.Forms.BindingExpression.Apply (System.Boolean fromTarget) [0x0003e] in D:\agent_work\1\s\Xamarin.Forms.Core\BindingExpression.cs:56
07-19 15:11:19.807 I/MonoDroid(21263): at Xamarin.Forms.BindingExpression+BindingExpressionPart.<PropertyChanged>b__47_0 () [0x00000] in D:\agent_work\1\s\Xamarin.Forms.Core\BindingExpression.cs:547
07-19 15:11:19.807 I/MonoDroid(21263): at Java.Lang.Thread+RunnableImplementor.Run () [0x00008] in <263adecfa58f4c449f1ff56156d886fd>:0
07-19 15:11:19.807 I/MonoDroid(21263): at Java.Lang.IRunnableInvoker.n_Run (System.IntPtr jnienv, System.IntPtr native__this) [0x00008] in <263adecfa58f4c449f1ff56156d886fd>:0
07-19 15:11:19.807 I/MonoDroid(21263): at (wrapper dynamic-method) System.Object.1a7d831e-faf9-4352-8714-9eaa2e173a53(intptr,intptr)