diff --git a/public/components/notebooks/components/helpers/__tests__/__snapshots__/modal_containers.test.tsx.snap b/public/components/notebooks/components/helpers/__tests__/__snapshots__/modal_containers.test.tsx.snap
index f9b4bdd75b..ff1a3680a0 100644
--- a/public/components/notebooks/components/helpers/__tests__/__snapshots__/modal_containers.test.tsx.snap
+++ b/public/components/notebooks/components/helpers/__tests__/__snapshots__/modal_containers.test.tsx.snap
@@ -117,6 +117,7 @@ exports[`modal_containers spec render get custom modal 1`] = `
       </EuiSmallButtonEmpty>
       <EuiSmallButton
         data-test-subj="custom-input-modal-confirm-button"
+        fill={true}
         onClick={[Function]}
       >
         Confirm
diff --git a/public/components/notebooks/components/helpers/custom_modals/__tests__/__snapshots__/custom_input_modal.test.tsx.snap b/public/components/notebooks/components/helpers/custom_modals/__tests__/__snapshots__/custom_input_modal.test.tsx.snap
index 7318c2cb0d..4f15d856d0 100644
--- a/public/components/notebooks/components/helpers/custom_modals/__tests__/__snapshots__/custom_input_modal.test.tsx.snap
+++ b/public/components/notebooks/components/helpers/custom_modals/__tests__/__snapshots__/custom_input_modal.test.tsx.snap
@@ -46,6 +46,7 @@ exports[`<CustomInputModal /> spec renders the component 1`] = `
       </EuiSmallButtonEmpty>
       <EuiSmallButton
         data-test-subj="custom-input-modal-confirm-button"
+        fill={true}
         onClick={[Function]}
       >
         Confirm
@@ -101,6 +102,7 @@ exports[`<CustomInputModal /> spec renders the component 2`] = `
       </EuiSmallButtonEmpty>
       <EuiSmallButton
         data-test-subj="custom-input-modal-confirm-button"
+        fill={true}
         onClick={[Function]}
       >
         Confirm
diff --git a/public/components/notebooks/components/helpers/custom_modals/custom_input_modal.tsx b/public/components/notebooks/components/helpers/custom_modals/custom_input_modal.tsx
index bbf97e0f57..a3fdaea88c 100644
--- a/public/components/notebooks/components/helpers/custom_modals/custom_input_modal.tsx
+++ b/public/components/notebooks/components/helpers/custom_modals/custom_input_modal.tsx
@@ -90,6 +90,7 @@ export const CustomInputModal = (props: CustomInputModalProps) => {
           <EuiSmallButton
             data-test-subj="custom-input-modal-confirm-button"
             onClick={() => runModal(value)}
+            fill
           >
             {btn2txt}
           </EuiSmallButton>