diff --git a/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts b/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts
index 340e83c9..6128c836 100644
--- a/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts
+++ b/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts
@@ -402,6 +402,22 @@ export class WebglCharAtlas implements IDisposable {
       this._tmpCtx.fillText(chars, padding, padding + this._config.scaledCharHeight);
     }
 
+    // If this charcater is underscore and beyond the cell bounds, shift it up until it is visible,
+    // try for a maximum of 5 pixels.
+    if (chars === '_' && !this._config.allowTransparency) {
+      let isBeyondCellBounds = clearColor(this._tmpCtx.getImageData(padding, padding, this._config.scaledCellWidth, this._config.scaledCellHeight), backgroundColor);
+      if (isBeyondCellBounds) {
+        for (let offset = 1; offset <= 5; offset++) {
+          this._tmpCtx.clearRect(0, 0, this._tmpCanvas.width, this._tmpCanvas.height);
+          this._tmpCtx.fillText(chars, padding, padding + this._config.scaledCharHeight - offset);
+          isBeyondCellBounds = clearColor(this._tmpCtx.getImageData(padding, padding, this._config.scaledCellWidth, this._config.scaledCellHeight), backgroundColor);
+          if (!isBeyondCellBounds) {
+            break;
+          }
+        }
+      }
+    }
+
     // Draw underline and strikethrough
     if (underline || strikethrough) {
       const lineWidth = Math.max(1, Math.floor(this._config.fontSize / 10));
@@ -443,7 +459,7 @@ export class WebglCharAtlas implements IDisposable {
       return NULL_RASTERIZED_GLYPH;
     }
 
-    const rasterizedGlyph = this._findGlyphBoundingBox(imageData, this._workBoundingBox, allowedWidth, isPowerlineGlyph);
+    const rasterizedGlyph = this._findGlyphBoundingBox(imageData, this._workBoundingBox, allowedWidth, isPowerlineGlyph, drawSuccess);
     const clippedImageData = this._clipImageData(imageData, this._workBoundingBox);
 
     // Check if there is enough room in the current row and go to next if needed
@@ -476,7 +492,7 @@ export class WebglCharAtlas implements IDisposable {
    * @param imageData The image data to read.
    * @param boundingBox An IBoundingBox to put the clipped bounding box values.
    */
-  private _findGlyphBoundingBox(imageData: ImageData, boundingBox: IBoundingBox, allowedWidth: number, restrictedGlyph: boolean): IRasterizedGlyph {
+  private _findGlyphBoundingBox(imageData: ImageData, boundingBox: IBoundingBox, allowedWidth: number, restrictedGlyph: boolean, customGlyph: boolean): IRasterizedGlyph {
     boundingBox.top = 0;
     const height = restrictedGlyph ? this._config.scaledCharHeight : this._tmpCanvas.height;
     const width = restrictedGlyph ? this._config.scaledCharWidth : allowedWidth;
@@ -551,8 +567,8 @@ export class WebglCharAtlas implements IDisposable {
         y: (boundingBox.bottom - boundingBox.top + 1) / TEXTURE_HEIGHT
       },
       offset: {
-        x: -boundingBox.left + (restrictedGlyph ? 0 : TMP_CANVAS_GLYPH_PADDING),
-        y: -boundingBox.top + (restrictedGlyph ? 0 : TMP_CANVAS_GLYPH_PADDING)
+        x: -boundingBox.left + (restrictedGlyph ? 0 : TMP_CANVAS_GLYPH_PADDING) + (customGlyph ? Math.floor(this._config.letterSpacing / 2) : 0),
+        y: -boundingBox.top + (restrictedGlyph ? 0 : TMP_CANVAS_GLYPH_PADDING) + (customGlyph ? this._config.lineHeight === 1 ? 0 : Math.round((this._config.scaledCellHeight - this._config.scaledCharHeight) / 2) : 0)
       }
     };
   }
diff --git a/src/browser/renderer/atlas/DynamicCharAtlas.ts b/src/browser/renderer/atlas/DynamicCharAtlas.ts
index 883ebe78..a7237878 100644
--- a/src/browser/renderer/atlas/DynamicCharAtlas.ts
+++ b/src/browser/renderer/atlas/DynamicCharAtlas.ts
@@ -266,11 +266,10 @@ export class DynamicCharAtlas extends BaseCharAtlas {
     }
     // Draw the character
     this._tmpCtx.fillText(glyph.chars, 0, this._config.scaledCharHeight);
-    this._tmpCtx.restore();
 
     // clear the background from the character to avoid issues with drawing over the previous
     // character if it extends past it's bounds
-    const imageData = this._tmpCtx.getImageData(
+    let imageData = this._tmpCtx.getImageData(
       0, 0, this._config.scaledCharWidth, this._config.scaledCharHeight
     );
     let isEmpty = false;
@@ -278,6 +277,27 @@ export class DynamicCharAtlas extends BaseCharAtlas {
       isEmpty = clearColor(imageData, backgroundColor);
     }
 
+    // If this charcater is underscore and empty, shift it up until it is visible, try for a maximum
+    // of 5 pixels.
+    if (isEmpty && glyph.chars === '_' && !this._config.allowTransparency) {
+      for (let offset = 1; offset <= 5; offset++) {
+        // Draw the character
+        this._tmpCtx.fillText(glyph.chars, 0, this._config.scaledCharHeight - offset);
+
+        // clear the background from the character to avoid issues with drawing over the previous
+        // character if it extends past it's bounds
+        imageData = this._tmpCtx.getImageData(
+          0, 0, this._config.scaledCharWidth, this._config.scaledCharHeight
+        );
+        isEmpty = clearColor(imageData, backgroundColor);
+        if (!isEmpty) {
+          break;
+        }
+      }
+    }
+
+    this._tmpCtx.restore();
+
     // copy the data from imageData to _cacheCanvas
     const x = this._toCoordinateX(index);
     const y = this._toCoordinateY(index);