diff --git a/addons/xterm-addon-webgl/src/WebglRenderer.ts b/addons/xterm-addon-webgl/src/WebglRenderer.ts
index 29e97d6d..75b6230c 100644
--- a/addons/xterm-addon-webgl/src/WebglRenderer.ts
+++ b/addons/xterm-addon-webgl/src/WebglRenderer.ts
@@ -230,7 +230,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
       return;
     }
 
-    const atlas = acquireCharAtlas(this._terminal, this._colors, this.dimensions.scaledCharWidth, this.dimensions.scaledCharHeight);
+    const atlas = acquireCharAtlas(this._terminal, this._colors, this.dimensions.scaledCellWidth, this.dimensions.scaledCellHeight, this.dimensions.scaledCharWidth, this.dimensions.scaledCharHeight);
     if (!('getRasterizedGlyph' in atlas)) {
       throw new Error('The webgl renderer only works with the webgl char atlas');
     }
diff --git a/addons/xterm-addon-webgl/src/atlas/CharAtlasCache.ts b/addons/xterm-addon-webgl/src/atlas/CharAtlasCache.ts
index 5046006f..41114de0 100644
--- a/addons/xterm-addon-webgl/src/atlas/CharAtlasCache.ts
+++ b/addons/xterm-addon-webgl/src/atlas/CharAtlasCache.ts
@@ -28,10 +28,12 @@ const charAtlasCache: ICharAtlasCacheEntry[] = [];
 export function acquireCharAtlas(
   terminal: Terminal,
   colors: IColorSet,
+  scaledCellWidth: number,
+  scaledCellHeight: number,
   scaledCharWidth: number,
   scaledCharHeight: number
 ): WebglCharAtlas {
-  const newConfig = generateConfig(scaledCharWidth, scaledCharHeight, terminal, colors);
+  const newConfig = generateConfig(scaledCellWidth, scaledCellHeight, scaledCharWidth, scaledCharHeight, terminal, colors);
 
   // Check to see if the terminal already owns this config
   for (let i = 0; i < charAtlasCache.length; i++) {
diff --git a/addons/xterm-addon-webgl/src/atlas/CharAtlasUtils.ts b/addons/xterm-addon-webgl/src/atlas/CharAtlasUtils.ts
index 5496a500..e91c5fd1 100644
--- a/addons/xterm-addon-webgl/src/atlas/CharAtlasUtils.ts
+++ b/addons/xterm-addon-webgl/src/atlas/CharAtlasUtils.ts
@@ -13,7 +13,7 @@ const NULL_COLOR: IColor = {
   rgba: 0
 };
 
-export function generateConfig(scaledCharWidth: number, scaledCharHeight: number, terminal: Terminal, colors: IColorSet): ICharAtlasConfig {
+export function generateConfig(scaledCellWidth: number, scaledCellHeight: number, scaledCharWidth: number, scaledCharHeight: number, terminal: Terminal, colors: IColorSet): ICharAtlasConfig {
   // null out some fields that don't matter
   const clonedColors: IColorSet = {
     foreground: colors.foreground,
@@ -28,7 +28,10 @@ export function generateConfig(scaledCharWidth: number, scaledCharHeight: number
     contrastCache: colors.contrastCache
   };
   return {
+    customBlockAndBoxCharacters: terminal.getOption('customBlockAndBoxCharacters'),
     devicePixelRatio: window.devicePixelRatio,
+    scaledCellWidth,
+    scaledCellHeight,
     scaledCharWidth,
     scaledCharHeight,
     fontFamily: terminal.getOption('fontFamily'),
diff --git a/addons/xterm-addon-webgl/src/atlas/Types.d.ts b/addons/xterm-addon-webgl/src/atlas/Types.d.ts
index cd73393c..37384306 100644
--- a/addons/xterm-addon-webgl/src/atlas/Types.d.ts
+++ b/addons/xterm-addon-webgl/src/atlas/Types.d.ts
@@ -17,11 +17,14 @@ export interface IGlyphIdentifier {
 }
 
 export interface ICharAtlasConfig {
+  customBlockAndBoxCharacters: boolean;
   devicePixelRatio: number;
   fontSize: number;
   fontFamily: string;
   fontWeight: FontWeight;
   fontWeightBold: FontWeight;
+  scaledCellWidth: number;
+  scaledCellHeight: number;
   scaledCharWidth: number;
   scaledCharHeight: number;
   allowTransparency: boolean;
diff --git a/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts b/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts
index 5f729e28..8fd43e1e 100644
--- a/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts
+++ b/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts
@@ -12,6 +12,7 @@ import { IColor } from 'browser/Types';
 import { IDisposable } from 'xterm';
 import { AttributeData } from 'common/buffer/AttributeData';
 import { channels, rgba } from 'browser/Color';
+import { tryDrawCustomChar } from 'browser/renderer/BoxAndBlockCharacters';
 
 // In practice we're probably never going to exhaust a texture this large. For debugging purposes,
 // however, it can be useful to set this to a really tiny value, to verify that LRU eviction works.
@@ -390,8 +391,16 @@ export class WebglCharAtlas implements IDisposable {
     // For powerline glyphs left/top padding is excluded (https://github.com/microsoft/vscode/issues/120129)
     const padding = isPowerlineGlyph ? 0 : TMP_CANVAS_GLYPH_PADDING;
 
+    // Draw custom characters if applicable
+    let drawSuccess = false;
+    if (this._config.customBlockAndBoxCharacters !== false) {
+      drawSuccess = tryDrawCustomChar(this._tmpCtx, chars, TMP_CANVAS_GLYPH_PADDING, TMP_CANVAS_GLYPH_PADDING, this._config.scaledCellWidth, this._config.scaledCellHeight, this._config.scaledCharWidth, this._config.scaledCharHeight);
+    }
+
     // Draw the character
-    this._tmpCtx.fillText(chars, padding, padding + this._config.scaledCharHeight);
+    if (!drawSuccess) {
+      this._tmpCtx.fillText(chars, padding, padding + this._config.scaledCharHeight);
+    }
 
     // Draw underline and strikethrough
     if (underline || strikethrough) {
diff --git a/addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts b/addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts
index cc210fd3..532836ee 100644
--- a/addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts
+++ b/addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts
@@ -92,7 +92,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     if (this._scaledCharWidth <= 0 && this._scaledCharHeight <= 0) {
       return;
     }
-    this._charAtlas = acquireCharAtlas(terminal, colorSet, this._scaledCharWidth, this._scaledCharHeight);
+    this._charAtlas = acquireCharAtlas(terminal, colorSet, this._scaledCellWidth, this._scaledCellHeight, this._scaledCharWidth, this._scaledCharHeight);
     this._charAtlas.warmUp();
   }
 
diff --git a/src/browser/Terminal.ts b/src/browser/Terminal.ts
index e702e61e..3ab343da 100644
--- a/src/browser/Terminal.ts
+++ b/src/browser/Terminal.ts
@@ -224,6 +224,7 @@ export class Terminal extends CoreTerminal implements ITerminal {
         // The DOM renderer needs a row refresh to update the cursor styles
         this.refresh(this.buffer.y, this.buffer.y);
         break;
+      case 'customBlockAndBoxCharacters':
       case 'drawBoldTextInBrightColors':
       case 'letterSpacing':
       case 'lineHeight':
diff --git a/src/browser/renderer/BaseRenderLayer.ts b/src/browser/renderer/BaseRenderLayer.ts
index e7116ed6..afa12bb2 100644
--- a/src/browser/renderer/BaseRenderLayer.ts
+++ b/src/browser/renderer/BaseRenderLayer.ts
@@ -264,7 +264,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     // Draw custom characters if applicable
     let drawSuccess = false;
     if (this._optionsService.options.customBlockAndBoxCharacters !== false) {
-      drawSuccess = tryDrawCustomChar(this._ctx, cell.getChars(), x, y, this._scaledCellWidth, this._scaledCellHeight, this._scaledCharLeft, this._scaledCharTop);
+      drawSuccess = tryDrawCustomChar(this._ctx, cell.getChars(), x * this._scaledCellWidth, y * this._scaledCellHeight, this._scaledCellWidth, this._scaledCellHeight, this._scaledCharLeft, this._scaledCharTop);
     }
 
     // Draw the character
@@ -388,7 +388,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     // Draw custom characters if applicable
     let drawSuccess = false;
     if (this._optionsService.options.customBlockAndBoxCharacters !== false) {
-      drawSuccess = tryDrawCustomChar(this._ctx, cell.getChars(), x, y, this._scaledCellWidth, this._scaledCellHeight, this._scaledCharLeft, this._scaledCharTop);
+      drawSuccess = tryDrawCustomChar(this._ctx, cell.getChars(), x * this._scaledCellWidth, y * this._scaledCellHeight, this._scaledCellWidth, this._scaledCellHeight, this._scaledCharLeft, this._scaledCharTop);
     }
 
     // Draw the character
diff --git a/src/browser/renderer/BoxAndBlockCharacters.ts b/src/browser/renderer/BoxAndBlockCharacters.ts
index fd897675..b38199ad 100644
--- a/src/browser/renderer/BoxAndBlockCharacters.ts
+++ b/src/browser/renderer/BoxAndBlockCharacters.ts
@@ -288,8 +288,8 @@ export const boxDrawingDefinitions: { [character: string]: { [fontWeight: number
 export function tryDrawCustomChar(
   ctx: CanvasRenderingContext2D,
   c: string,
-  x: number,
-  y: number,
+  xOffset: number,
+  yOffset: number,
   scaledCellWidth: number,
   scaledCellHeight: number,
   scaledCharLeft: number,
@@ -297,13 +297,13 @@ export function tryDrawCustomChar(
 ): boolean {
   const blockElementDefinition = blockElementDefinitions[c];
   if (blockElementDefinition) {
-    drawBlockElementChar(ctx, blockElementDefinition, x, y, scaledCellWidth, scaledCellHeight, scaledCharLeft, scaledCharTop);
+    drawBlockElementChar(ctx, blockElementDefinition, xOffset, yOffset, scaledCellWidth, scaledCellHeight, scaledCharLeft, scaledCharTop);
     return true;
   }
 
   const boxDrawingDefinition = boxDrawingDefinitions[c];
   if (boxDrawingDefinition) {
-    drawBoxDrawingChar(ctx, boxDrawingDefinition, x, y, scaledCellWidth, scaledCellHeight);
+    drawBoxDrawingChar(ctx, boxDrawingDefinition, xOffset, yOffset, scaledCellWidth, scaledCellHeight);
     return true;
   }
 
@@ -313,15 +313,16 @@ export function tryDrawCustomChar(
 function drawBlockElementChar(
   ctx: CanvasRenderingContext2D,
   charDefinition: IBlockVector[],
-  x: number,
-  y: number,
+  xOffset: number,
+  yOffset: number,
   scaledCellWidth: number,
   scaledCellHeight: number,
   scaledCharLeft: number,
   scaledCharTop: number
 ): void {
-  const xOffset = x * scaledCellWidth + scaledCharLeft;
-  const yOffset = y * scaledCellHeight + scaledCharTop;
+  // TODO: Scale to cell not char?
+  xOffset += scaledCharLeft;
+  yOffset += scaledCharTop;
   for (let i = 0; i < charDefinition.length; i++) {
     const box = charDefinition[i];
     const xEighth = scaledCellWidth / 8;
@@ -378,13 +379,11 @@ function drawBlockElementChar(
 function drawBoxDrawingChar(
   ctx: CanvasRenderingContext2D,
   charDefinition: { [fontWeight: number]: string | ((xp: number, yp: number) => string) },
-  x: number,
-  y: number,
+  xOffset: number,
+  yOffset: number,
   scaledCellWidth: number,
   scaledCellHeight: number
 ): void {
-  const xOffset = x * scaledCellWidth;
-  const yOffset = y * scaledCellHeight;
   ctx.strokeStyle = ctx.fillStyle;
   for (const [fontWeight, instructions] of Object.entries(charDefinition)) {
     ctx.beginPath();