Steps to reproduce:
1. Open the attached project "TMPBug.zip"
2. Open Scenes>SampleScene
3. Enter the Play Mode
4. Click on the Input Field in the Game View
5. Type any symbol
6. Click on the Input Field in the Game View
7. Observe the Console window

Expected results: No errors are thrown
Actual result: "IndexOutOfRangeException" is thrown

Reproducible with: 2.1.6 (2019.4.30f1), 3.2.0-pre.1 (2020.3.17f1, 2021.1.19f1, 2021.2.0b8, 2022.1.0a7)

Full error:
IndexOutOfRangeException: Index was outside the bounds of the array.
TMPro.TMP_TextUtilities.FindNearestCharacterOnLine (TMPro.TMP_Text text, UnityEngine.Vector3 position, System.Int32 line, UnityEngine.Camera camera, System.Boolean visibleOnly) (at Library/PackageCache/com.unity.textmeshpro@2.1.6/Scripts/Runtime/TMP_TextUtilities.cs:242)
TMPro.TMP_TextUtilities.GetCursorIndexFromPosition (TMPro.TMP_Text textComponent, UnityEngine.Vector3 position, UnityEngine.Camera camera, TMPro.CaretPosition& cursor) (at Library/PackageCache/com.unity.textmeshpro@2.1.6/Scripts/Runtime/TMP_TextUtilities.cs:146)
TMPro.TMP_InputField.OnPointerDown (UnityEngine.EventSystems.PointerEventData eventData) (at Library/PackageCache/com.unity.textmeshpro@2.1.6/Scripts/Runtime/TMP_InputField.cs:1805)
UnityEngine.EventSystems.ExecuteEvents.Execute (UnityEngine.EventSystems.IPointerDownHandler handler, UnityEngine.EventSystems.BaseEventData eventData) (at Library/PackageCache/com.unity.ugui@1.0.0/Runtime/EventSystem/ExecuteEvents.cs:36)
UnityEngine.EventSystems.ExecuteEvents.Execute[T] (UnityEngine.GameObject target, UnityEngine.EventSystems.BaseEventData eventData, UnityEngine.EventSystems.ExecuteEvents+EventFunction`1[T1] functor) (at Library/PackageCache/com.unity.ugui@1.0.0/Runtime/EventSystem/ExecuteEvents.cs:261)
UnityEngine.EventSystems.EventSystem:Update() (at Library/PackageCache/com.unity.ugui@1.0.0/Runtime/EventSystem/EventSystem.cs:377)