diff --git a/src/vs/workbench/contrib/terminal/browser/terminalConfigHelper.ts b/src/vs/workbench/contrib/terminal/browser/terminalConfigHelper.ts
index fd27c75f4f7..552d69c615e 100644
--- a/src/vs/workbench/contrib/terminal/browser/terminalConfigHelper.ts
+++ b/src/vs/workbench/contrib/terminal/browser/terminalConfigHelper.ts
@@ -191,15 +191,16 @@ export class TerminalConfigHelper extends Disposable implements IBrowserTerminal
 		}
 
 		// Get the character dimensions from xterm if it's available
-		if (xtermCore) {
-			if (xtermCore._renderService && xtermCore._renderService.dimensions?.css.cell.width && xtermCore._renderService.dimensions?.css.cell.height) {
+		if (xtermCore?._renderService?._renderer.value) {
+			const cellDims = xtermCore._renderService.dimensions.css.cell;
+			if (cellDims?.width && cellDims?.height) {
 				return {
 					fontFamily,
 					fontSize,
 					letterSpacing,
 					lineHeight,
-					charHeight: xtermCore._renderService.dimensions.css.cell.height / lineHeight,
-					charWidth: xtermCore._renderService.dimensions.css.cell.width - Math.round(letterSpacing) / window.devicePixelRatio
+					charHeight: cellDims.height / lineHeight,
+					charWidth: cellDims.width - Math.round(letterSpacing) / window.devicePixelRatio
 				};
 			}
 		}
diff --git a/src/vs/workbench/contrib/terminal/browser/xterm-private.d.ts b/src/vs/workbench/contrib/terminal/browser/xterm-private.d.ts
index 7be81115a66..77592d9e033 100644
--- a/src/vs/workbench/contrib/terminal/browser/xterm-private.d.ts
+++ b/src/vs/workbench/contrib/terminal/browser/xterm-private.d.ts
@@ -39,7 +39,9 @@ export interface IXtermCore {
 			}
 		},
 		_renderer: {
-			_renderLayers?: any[];
+			value?: {
+				_renderLayers?: any[];
+			}
 		};
 		_handleIntersectionChange: any;
 	};
diff --git a/src/vs/workbench/contrib/terminal/browser/xterm/xtermTerminal.ts b/src/vs/workbench/contrib/terminal/browser/xterm/xtermTerminal.ts
index 8ed7b82393d..fde61f25751 100644
--- a/src/vs/workbench/contrib/terminal/browser/xterm/xtermTerminal.ts
+++ b/src/vs/workbench/contrib/terminal/browser/xterm/xtermTerminal.ts
@@ -839,10 +839,10 @@ export class XtermTerminal extends Disposable implements IXtermTerminal, IDetach
 
 	private async _measureRenderTime(): Promise<void> {
 		const frameTimes: number[] = [];
-		if (!this._core._renderService?._renderer._renderLayers) {
+		if (!this._core._renderService?._renderer.value?._renderLayers) {
 			return;
 		}
-		const textRenderLayer = this._core._renderService._renderer._renderLayers[0];
+		const textRenderLayer = this._core._renderService._renderer.value._renderLayers[0];
 		const originalOnGridChanged = textRenderLayer?.onGridChanged;
 		const evaluateCanvasRenderer = () => {
 			// Discard first frame time as it's normal to take longer