Missed a few things.

Sane Eric's UI/Scriptable Variables/FloatVariableInput.cs

 using System;
 using UnityEngine;
 using UnityEngine.Events;
-using UnityEngine.UI;
+using TMPro;
 using Shared.ScriptableVariables;
 
 namespace Shared.SEUI {
@@ -12,7 +12,7 @@ namespace Shared.SEUI {
     public FloatVariable variable;
 
     [Tooltip("The input UI to edit the variable's value with")]
-    public InputField input;
+    public TMP_InputField input;
 
     // Temporary callback to bridge value changes in the UI and the variable
     private UnityAction<string> valueConverter;
@@ -20,7 +20,7 @@ namespace Shared.SEUI {
     //---------------------------------------------------------------------------
     void Start() {
       // Make sure the input handles the right content type
-      input.contentType = InputField.ContentType.DecimalNumber;
+      input.contentType = TMP_InputField.ContentType.DecimalNumber;
     }
 
     //---------------------------------------------------------------------------

Sane Eric's UI/Scriptable Variables/IntVariableInput.cs

 using System;
 using UnityEngine;
 using UnityEngine.Events;
-using UnityEngine.UI;
+using TMPro;
 using Shared.ScriptableVariables;
 
 namespace Shared.SEUI {
@@ -12,7 +12,7 @@ namespace Shared.SEUI {
     public IntVariable variable;
 
     [Tooltip("The input UI to edit the variable's value with")]
-    public InputField input;
+    public TMP_InputField input;
 
     // Temporary callback to bridge value changes in the UI and the variable
     private UnityAction<string> valueConverter;
@@ -20,7 +20,7 @@ namespace Shared.SEUI {
     //---------------------------------------------------------------------------
     void Start() {
       // Make sure the input handles the right content type
-      input.contentType = InputField.ContentType.IntegerNumber;
+      input.contentType = TMP_InputField.ContentType.IntegerNumber;
     }
 
     //---------------------------------------------------------------------------

Sane Eric's UI/Shared.SEUI.asmdef

@@ -4,7 +4,7 @@
         "GUID:6735fe1fe1dbd994a96eb9d888b81400",
 		"Unity.TextMeshPro"
     ],
-    "optionalUnityReferences": [ "TestAssemblies" ],
+    "optionalUnityReferences": [],
     "includePlatforms": [],
     "excludePlatforms": [],
     "allowUnsafeCode": false,