diff --git a/src/svelte/src/components/DataDisplays/CustomByteDisplay/BinaryData.ts b/src/svelte/src/components/DataDisplays/CustomByteDisplay/BinaryData.ts
index 2d7b0b4b3..ff45bad7d 100644
--- a/src/svelte/src/components/DataDisplays/CustomByteDisplay/BinaryData.ts
+++ b/src/svelte/src/components/DataDisplays/CustomByteDisplay/BinaryData.ts
@@ -17,14 +17,15 @@
 
 import { SimpleWritable } from '../../../stores/localStore'
 import {
+  dataDisplayLineCount,
   type BytesPerRow,
   type RadixValues,
-  data_dislay_line_amount,
 } from '../../../stores/configuration'
 import {
   radixBytePad,
   viewport_offset_to_line_num,
 } from '../../../utilities/display'
+
 import { get } from 'svelte/store'
 
 export const BYTE_ACTION_DIV_OFFSET: number = 24
@@ -38,7 +39,7 @@ export type EditAction =
 
 export type ByteValue = {
   offset: number
-  text: string | undefined
+  text: string
   value: number
 }
 
@@ -112,9 +113,7 @@ export class ViewportDataStore_t extends SimpleWritable<ViewportData_t> {
   public upperFetchBoundary(bytesPerRow: BytesPerRow): number {
     const store = this.storeData()
     const boundary =
-      store.fileOffset +
-      store.length -
-      get(data_dislay_line_amount) * bytesPerRow
+      store.fileOffset + store.length - get(dataDisplayLineCount) * bytesPerRow
 
     return boundary
   }
@@ -122,7 +121,7 @@ export class ViewportDataStore_t extends SimpleWritable<ViewportData_t> {
   public lineTopMax(bytesPerRow: BytesPerRow): number {
     const vpMaxOffset = Math.max(
       0,
-      this.storeData().length - get(data_dislay_line_amount) * bytesPerRow
+      this.storeData().length - get(dataDisplayLineCount) * bytesPerRow
     )
     const vpLineTopMax = viewport_offset_to_line_num(
       vpMaxOffset + this.storeData().fileOffset,
diff --git a/src/svelte/src/components/DataDisplays/CustomByteDisplay/DataLineFeed.svelte b/src/svelte/src/components/DataDisplays/CustomByteDisplay/DataLineFeed.svelte
index 00c7acd4d..0910ee21b 100644
--- a/src/svelte/src/components/DataDisplays/CustomByteDisplay/DataLineFeed.svelte
+++ b/src/svelte/src/components/DataDisplays/CustomByteDisplay/DataLineFeed.svelte
@@ -29,12 +29,10 @@ limitations under the License.
     editorActionsAllowed,
     dataFeedLineTop,
     seekOffsetInput,
-    tooltipsEnabled,
-    viewport,
+    dataDisplayLineCount
   } from '../../../stores'
   import {
     EditByteModes,
-    data_dislay_line_amount,
     type RadixValues,
     EditActionRestrictions,
     VIEWPORT_SCROLL_INCREMENT,
@@ -94,7 +92,7 @@ limitations under the License.
       if (fetchBound > $fileMetrics.computedSize)
         return (
           ($fileMetrics.computedSize / $bytesPerRow) * $bytesPerRow -
-          $data_dislay_line_amount * $bytesPerRow
+          $dataDisplayLineCount * $bytesPerRow
         )
 
       return fetchBound
@@ -128,7 +126,7 @@ limitations under the License.
   }
   const INCREMENT_SEGMENT = () => {
     $seekOffsetInput = line_num_to_file_offset(
-      $dataFeedLineTop + $data_dislay_line_amount,
+      $dataFeedLineTop + $dataDisplayLineCount,
       viewportData.fileOffset,
       $bytesPerRow
     ).toString(addressRadix)
@@ -136,7 +134,7 @@ limitations under the License.
   }
   const DECREMENT_SEGMENT = () => {
     $seekOffsetInput = line_num_to_file_offset(
-      $dataFeedLineTop - $data_dislay_line_amount,
+      $dataFeedLineTop - $dataDisplayLineCount,
       viewportData.fileOffset,
       $bytesPerRow
     ).toString(addressRadix)
@@ -181,7 +179,7 @@ limitations under the License.
     INCREMENT = 1,
   }
 
-  let height = `calc(${$data_dislay_line_amount} * 20)px`
+  let height = `calc(${$dataDisplayLineCount} * 20)px`
   let viewportLines: Array<ViewportLineData> = []
   let viewportDataContainer: HTMLDivElement
   let selectedByteElement: HTMLDivElement
@@ -201,9 +199,9 @@ limitations under the License.
   $: {
     totalLinesPerFilesize = Math.ceil($fileMetrics.computedSize / $bytesPerRow)
     totalLinesPerViewport = Math.ceil(viewportData.data.length / $bytesPerRow)
-    lineTopMaxFile = Math.max(totalLinesPerFilesize - $data_dislay_line_amount, 0)
+    lineTopMaxFile = Math.max(totalLinesPerFilesize - $dataDisplayLineCount, 0)
     lineTopMaxViewport = Math.max(
-      totalLinesPerViewport - $data_dislay_line_amount,
+      totalLinesPerViewport - $dataDisplayLineCount,
       0
     )
 
@@ -253,14 +251,14 @@ limitations under the License.
     startIndex: number,
     dataRadix: RadixValues,
     addressRadix: RadixValues,
-    endIndex: number = startIndex + ($data_dislay_line_amount - 1)
-  ): Array<ViewportLineData> {
-    let ret = []
+    endIndex: number = startIndex + ($dataDisplayLineCount - 1)
+  ): ViewportLineData[] {
+    let ret:ViewportLineData[] = []
     for (let i = startIndex; i <= endIndex; i++) {
       const viewportLineOffset = i * $bytesPerRow
       const fileOffset = viewportLineOffset + viewportData.fileOffset
 
-      let bytes: Array<ByteValue> = []
+      let bytes: ByteValue[] = []
       const highlight = i % 2 === 0
 
       for (let bytePos = 0; bytePos < $bytesPerRow; bytePos++) {
@@ -444,7 +442,7 @@ limitations under the License.
         ($fileMetrics.computedSize * (percentageTraversed / 100.0)) /
           $bytesPerRow
       ) * $bytesPerRow
-    const firstPageThreshold = $bytesPerRow * $data_dislay_line_amount
+    const firstPageThreshold = $bytesPerRow * $dataDisplayLineCount
     const lastPageThreshold = $fileMetrics.computedSize - firstPageThreshold
     if (offset <= firstPageThreshold) {
       // scroll to the top because we are somewhere in the first page
@@ -570,7 +568,7 @@ limitations under the License.
       selectionActive={$selectionDataStore.active}
       currentLine={$dataFeedLineTop}
       fileOffset={viewportData.fileOffset}
-      maxDisplayLines={$data_dislay_line_amount}
+      maxDisplayLines={$dataDisplayLineCount}
       bind:percentageTraversed
       on:indicatorClicked={handleClickedIndicator}
     />
@@ -590,7 +588,7 @@ limitations under the License.
         fn={INCREMENT_SEGMENT}
         disabledBy={disableIncrement}
         width="30pt"
-        description="Increment offset by {$data_dislay_line_amount *
+        description="Increment offset by {$dataDisplayLineCount *
           $bytesPerRow} bytes"
         tooltipAlwaysEnabled={true}
       >
@@ -624,7 +622,7 @@ limitations under the License.
         fn={DECREMENT_SEGMENT}
         disabledBy={disableDecrement}
         width="30pt"
-        description="Decrement offset by {$data_dislay_line_amount *
+        description="Decrement offset by {$dataDisplayLineCount *
           $bytesPerRow} bytes"
         tooltipAlwaysEnabled={true}
       >
@@ -646,7 +644,7 @@ limitations under the License.
       <span class="separator" />
       <Button
         fn={() => { 
-            update_num_lines_displayed($data_dislay_line_amount+1) 
+            update_num_lines_displayed($dataDisplayLineCount+1) 
             viewportLines = generate_line_data(
               $dataFeedLineTop,
               dataRadix,
@@ -654,8 +652,8 @@ limitations under the License.
               )
           }
         }
-        disabledBy={ ($data_dislay_line_amount*$bytesPerRow >= 512) }
-        description={"Increment display lines (" + ($data_dislay_line_amount+1) + ")"}
+        disabledBy={ ($dataDisplayLineCount*$bytesPerRow >= 512) }
+        description={"Increment display lines (" + ($dataDisplayLineCount+1) + ")"}
         tooltipAlwaysEnabled={true}
         width="30pt"
       >
@@ -665,7 +663,7 @@ limitations under the License.
       </Button>
       <Button
         fn={() => { 
-            update_num_lines_displayed($data_dislay_line_amount-1) 
+            update_num_lines_displayed($dataDisplayLineCount-1) 
             viewportLines = generate_line_data(
               $dataFeedLineTop,
               dataRadix,
@@ -673,8 +671,8 @@ limitations under the License.
               )
           }
         }
-        disabledBy={$data_dislay_line_amount === 1}
-        description={"Decrement display lines (" + ($data_dislay_line_amount-1) + ")"}
+        disabledBy={$dataDisplayLineCount === 1}
+        description={"Decrement display lines (" + ($dataDisplayLineCount-1) + ")"}
         tooltipAlwaysEnabled={true}
         width="30pt"
       >
diff --git a/src/svelte/src/stores/configuration.ts b/src/svelte/src/stores/configuration.ts
index 658409ee7..e82998f8f 100644
--- a/src/svelte/src/stores/configuration.ts
+++ b/src/svelte/src/stores/configuration.ts
@@ -15,7 +15,7 @@
  * limitations under the License.
  */
 
-import { get, writable } from 'svelte/store'
+import { dataDisplayLineCount } from '.'
 
 export type Radixes = 'Hexadecimal' | 'Decimal' | 'Octal' | 'Binary'
 
@@ -114,9 +114,11 @@ export const VIEWPORT_CAPACITY_MAX = 16 * 64 // 1024, Ωedit maximum viewport si
 // Offset shift amount on viewport data fetch
 export const VIEWPORT_SCROLL_INCREMENT = VIEWPORT_CAPACITY_MAX / 2
 
-// Number of bytes to display in the viewport
-export const data_dislay_line_amount = writable(20)
 export function update_num_lines_displayed(line_num: number) {
-  data_dislay_line_amount.set(line_num)
+  dataDisplayLineCount.set(line_num)
+}
+export function can_update_num_lines_displayed(line_num: number): boolean {
+  return false
 }
 export const DATA_PROFILE_MAX_LENGTH = 10_000_000
+export { dataDisplayLineCount }
diff --git a/src/svelte/src/stores/index.ts b/src/svelte/src/stores/index.ts
index 5c7eaee37..f8264fd73 100644
--- a/src/svelte/src/stores/index.ts
+++ b/src/svelte/src/stores/index.ts
@@ -43,6 +43,7 @@ import {
   type RadixValues,
   type BytesPerRow,
   EditActionRestrictions,
+  VIEWPORT_SCROLL_INCREMENT,
 } from './configuration'
 
 export class SelectionData_t {
@@ -147,6 +148,19 @@ export const sizeHumanReadable = writable(false)
 // tracks the start and end offsets of the current selection
 export const selectionDataStore = new SelectionData()
 
+// Number of bytes to display in the viewport
+export const dataDisplayLineCount = writable(20)
+
+export const MAX_DATA_DISPLAY_LINE_COUNT = derived(
+  [dataDisplayLineCount, bytesPerRow],
+  ([$dataDisplayLineCount, $bytesPerRow]) => {
+    if ($dataDisplayLineCount * $bytesPerRow >= VIEWPORT_SCROLL_INCREMENT)
+      return false
+    if ($dataDisplayLineCount === 1) return false
+    return true
+  }
+)
+
 // Can the user's selection derive both edit modes?
 export const regularSizedFile = derived(fileMetrics, ($fileMetrics) => {
   return $fileMetrics.computedSize >= 2
@@ -287,8 +301,8 @@ export const editedByteIsOriginalByte = derived(
   [editorSelection, selectedByte, focusedViewportId],
   ([$editorSelection, $selectedByte, $focusedViewportId]) => {
     return $focusedViewportId === 'logical'
-      ? $editorSelection === $selectedByte.text
-      : $editorSelection.toLowerCase() === $selectedByte.text.toLowerCase()
+      ? $editorSelection === $selectedByte.text!
+      : $editorSelection.toLowerCase() === $selectedByte.text!.toLowerCase()
   }
 )