diff --git a/InvenTree/company/templates/company/index.html b/InvenTree/company/templates/company/index.html
index f110950c0b..ae3e191bc1 100644
--- a/InvenTree/company/templates/company/index.html
+++ b/InvenTree/company/templates/company/index.html
@@ -15,7 +15,9 @@ InvenTree | {% trans "Supplier List" %}
 {% if pagetype == 'manufacturers' and roles.purchase_order.add or pagetype == 'suppliers' and roles.purchase_order.add or pagetype == 'customers' and roles.sales_order.add %}
 <div id='button-toolbar'>
     <div class='btn-group'>
-        <button type='button' class="btn btn-success" id='new-company'>{{ button_text }}</button>
+        <button type='button' class="btn btn-success" id='new-company'>
+            <span class='fas fa-plus-circle'></span> {{ button_text }}
+        </button>
     </div>
 </div>
 {% endif %}
diff --git a/InvenTree/part/api.py b/InvenTree/part/api.py
index 496153a6d0..c96cff6da5 100644
--- a/InvenTree/part/api.py
+++ b/InvenTree/part/api.py
@@ -186,18 +186,29 @@ class PartTestTemplateList(generics.ListCreateAPIView):
 
 
 class PartThumbs(generics.ListAPIView):
-    """ API endpoint for retrieving information on available Part thumbnails """
+    """
+    API endpoint for retrieving information on available Part thumbnails
+    """
 
+    queryset = Part.objects.all()
     serializer_class = part_serializers.PartThumbSerializer
 
+    def get_queryset(self):
+
+        queryset = super().get_queryset()
+
+        # Get all Parts which have an associated image
+        queryset = queryset.exclude(image='')
+        
+        return queryset
+
     def list(self, request, *args, **kwargs):
         """
         Serialize the available Part images.
         - Images may be used for multiple parts!
         """
 
-        # Get all Parts which have an associated image
-        queryset = Part.objects.all().exclude(image='')
+        queryset = self.get_queryset()
 
         # TODO - We should return the thumbnails here, not the full image!
 
diff --git a/InvenTree/part/test_api.py b/InvenTree/part/test_api.py
index 328ad3ef9e..131936b8bd 100644
--- a/InvenTree/part/test_api.py
+++ b/InvenTree/part/test_api.py
@@ -241,6 +241,17 @@ class PartAPITest(APITestCase):
 
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
+    def test_get_thumbs(self):
+        """
+        Return list of part thumbnails
+        """
+
+        url = reverse('api-part-thumbs')
+
+        response = self.client.get(url)
+
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+
 
 class PartAPIAggregationTest(APITestCase):
     """
diff --git a/InvenTree/stock/views.py b/InvenTree/stock/views.py
index 2e45ceb00e..1d58647d5a 100644
--- a/InvenTree/stock/views.py
+++ b/InvenTree/stock/views.py
@@ -1505,8 +1505,10 @@ class StockItemCreate(AjaxCreateView):
             # form.fields['part'].widget = HiddenInput()
 
             # Trackable parts get special consideration:
-            form.fields['delete_on_deplete'].disabled = not part.trackable
-            form.fields['serial_numbers'].disabled = not part.trackable
+            if part.trackable:
+                form.fields['delete_on_deplete'].disabled = True
+            else:
+                form.fields['serial_numbers'].disabled = True
 
             # If the part is NOT purchaseable, hide the supplier_part field
             if not part.purchaseable:
diff --git a/requirements.txt b/requirements.txt
index 6e634328ae..5d2917b57d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -18,8 +18,8 @@ django-import-export==2.0.0     # Data import / export for admin interface
 django-cleanup==4.0.0           # Manage deletion of old / unused uploaded files
 django-qr-code==1.2.0           # Generate QR codes
 flake8==3.8.3                   # PEP checking
-coverage==5.2.1                 # Unit test coverage
-python-coveralls==2.9.1         # Coveralls linking (for Travis)
+coverage==5.3                   # Unit test coverage
+coveralls==2.1.2                # Coveralls linking (for Travis)
 rapidfuzz==0.7.6                # Fuzzy string matching
 django-stdimage==5.1.1          # Advanced ImageField management
 django-tex==1.1.7               # LaTeX PDF export