[BUG] App crash with autofill on some applications

Checks

• I have read the FAQ section, searched the open issues, and still think this is a new bug.

Describe the bug you encountered:

When typing OTP/PIN/fingerprint on some applications, the Keepass2Android app crashes and show a ANR dialog.

This situation happen mostly with the banking app Poste Italiane, like in the following screenshot.

Here you can find the error verbose log:

01/01/2024 22:40:48:774 -- parsing autofillStructure... 01/01/2024 22:40:48:789 -- System.ArgumentNullException: Value cannot be null. Parameter name: key at System.Collections.Generic.Dictionary2[TKey,TValue].FindEntry (TKey key) [0x00008] in <4087c528abc04d8290db635003aa826f>:0
at System.Collections.Generic.Dictionary2[TKey,TValue].TryGetValue (TKey key, TValue& value) [0x00000] in <4087c528abc04d8290db635003aa826f>:0 at Kp2aAutofillParser.AutofillHintsHelper.ToCanonicalHint (System.String hint) [0x00000] in <b3fff3fe4c1d4e8994fd67a2f50d0277>:0 at System.Linq.Enumerable+SelectEnumerableIterator2[TSource,TResult].MoveNext () [0x00048] in <052d4ffc295b472ebae9750a0d92739d>:0
at System.Collections.Generic.HashSet1[T].UnionWith (System.Collections.Generic.IEnumerable1[T] other) [0x00026] in <052d4ffc295b472ebae9750a0d92739d>:0
at System.Collections.Generic.HashSet1[T]..ctor (System.Collections.Generic.IEnumerable1[T] collection, System.Collections.Generic.IEqualityComparer1[T] comparer) [0x0004c] in <052d4ffc295b472ebae9750a0d92739d>:0 at System.Linq.Enumerable.ToHashSet[TSource] (System.Collections.Generic.IEnumerable1[T] source, System.Collections.Generic.IEqualityComparer1[T] comparer) [0x0000e] in <052d4ffc295b472ebae9750a0d92739d>:0 at System.Linq.Enumerable.ToHashSet[TSource] (System.Collections.Generic.IEnumerable1[T] source) [0x00000] in <052d4ffc295b472ebae9750a0d92739d>:0
at Kp2aAutofillParser.StructureParserBase1[FieldT].Parse (System.Boolean forFill, System.Boolean isManualRequest, Kp2aAutofillParser.AutofillView1[TField] autofillView) [0x000b3] in :0
at keepass2android.services.AutofillBase.StructureParser.Parse (System.Boolean forFill, System.Boolean isManualRequest, Kp2aAutofillParser.AutofillView1[TField] autofillView) [0x0000d] in <fb40c821fb5144dda464d1c7539af8a0>:0 at keepass2android.services.AutofillBase.StructureParser.ParseForFill (System.Boolean isManual) [0x00018] in <fb40c821fb5144dda464d1c7539af8a0>:0 at keepass2android.services.AutofillBase.AutofillServiceBase.OnFillRequest (Android.Service.Autofill.FillRequest request, Android.OS.CancellationSignal cancellationSignal, Android.Service.Autofill.FillCallback callback) [0x0009f] in <fb40c821fb5144dda464d1c7539af8a0>:0 at Android.Service.Autofill.AutofillService.n_OnFillRequest_Landroid_service_autofill_FillRequest_Landroid_os_CancellationSignal_Landroid_service_autofill_FillCallback_ (System.IntPtr jnienv, System.IntPtr native__this, System.IntPtr native_request, System.IntPtr native_cancellationSignal, System.IntPtr native__callback) [0x00020] in <3e1504268cb1422b8c7c2994fae408c2>:0 at Android.Runtime.JNINativeWrapper.Wrap_JniMarshal_PPLLL_V (_JniMarshal_PPLLL_V callback, System.IntPtr jnienv, System.IntPtr klazz, System.IntPtr p0, System.IntPtr p1, System.IntPtr p2) [0x00005] in <3e1504268cb1422b8c7c2994fae408c2>:0 01/01/2024 22:40:53:59 -- Creating application keepass2android.keepass2android. Version=197 01/01/2024 22:40:53:186 -- parsing autofillStructure... 01/01/2024 22:40:53:215 -- System.ArgumentNullException: Value cannot be null. Parameter name: key at System.Collections.Generic.Dictionary2[TKey,TValue].FindEntry (TKey key) [0x00008] in <4087c528abc04d8290db635003aa826f>:0
at System.Collections.Generic.Dictionary2[TKey,TValue].TryGetValue (TKey key, TValue& value) [0x00000] in <4087c528abc04d8290db635003aa826f>:0 at Kp2aAutofillParser.AutofillHintsHelper.ToCanonicalHint (System.String hint) [0x00000] in <b3fff3fe4c1d4e8994fd67a2f50d0277>:0 at System.Linq.Enumerable+SelectEnumerableIterator2[TSource,TResult].MoveNext () [0x00048] in <052d4ffc295b472ebae9750a0d92739d>:0
at System.Collections.Generic.HashSet1[T].UnionWith (System.Collections.Generic.IEnumerable1[T] other) [0x00026] in <052d4ffc295b472ebae9750a0d92739d>:0
at System.Collections.Generic.HashSet1[T]..ctor (System.Collections.Generic.IEnumerable1[T] collection, System.Collections.Generic.IEqualityComparer1[T] comparer) [0x0004c] in <052d4ffc295b472ebae9750a0d92739d>:0 at System.Linq.Enumerable.ToHashSet[TSource] (System.Collections.Generic.IEnumerable1[T] source, System.Collections.Generic.IEqualityComparer1[T] comparer) [0x0000e] in <052d4ffc295b472ebae9750a0d92739d>:0 at System.Linq.Enumerable.ToHashSet[TSource] (System.Collections.Generic.IEnumerable1[T] source) [0x00000] in <052d4ffc295b472ebae9750a0d92739d>:0
at Kp2aAutofillParser.StructureParserBase1[FieldT].Parse (System.Boolean forFill, System.Boolean isManualRequest, Kp2aAutofillParser.AutofillView1[TField] autofillView) [0x000b3] in :0
at keepass2android.services.AutofillBase.StructureParser.Parse (System.Boolean forFill, System.Boolean isManualRequest, Kp2aAutofillParser.AutofillView1[TField] autofillView) [0x0000d] in <fb40c821fb5144dda464d1c7539af8a0>:0 at keepass2android.services.AutofillBase.StructureParser.ParseForFill (System.Boolean isManual) [0x00018] in <fb40c821fb5144dda464d1c7539af8a0>:0 at keepass2android.services.AutofillBase.AutofillServiceBase.OnFillRequest (Android.Service.Autofill.FillRequest request, Android.OS.CancellationSignal cancellationSignal, Android.Service.Autofill.FillCallback callback) [0x0009f] in <fb40c821fb5144dda464d1c7539af8a0>:0 at Android.Service.Autofill.AutofillService.n_OnFillRequest_Landroid_service_autofill_FillRequest_Landroid_os_CancellationSignal_Landroid_service_autofill_FillCallback_ (System.IntPtr jnienv, System.IntPtr native__this, System.IntPtr native_request, System.IntPtr native_cancellationSignal, System.IntPtr native__callback) [0x00020] in <3e1504268cb1422b8c7c2994fae408c2>:0 at Android.Runtime.JNINativeWrapper.Wrap_JniMarshal_PPLLL_V (_JniMarshal_PPLLL_V callback, System.IntPtr jnienv, System.IntPtr klazz, System.IntPtr p0, System.IntPtr p1, System.IntPtr p2) [0x00005] in <3e1504268cb1422b8c7c2994fae408c2>:0

Describe what you expected to happen:

The Keepass2Android should ignore that kind of authentication screen or, at least, it should ask for credentials without crashing.

What version of Keepass2Android are you using?

1.09e-r7

Which version of Android are you on?

14

Start with Kp2aAutofillParser.AutofillHintsHelper.ToCanonicalHint and follow its callers through StructureParserBase.Parse and AutofillServiceBase.OnFillRequest. Reproduce an autofill request on Android 14 using the reported banking-app scenario, then verify that null hints no longer cause the crash and that the app ignores the authentication screen or requests credentials.