diff --git a/addons/xterm-addon-webgl/src/GlyphRenderer.ts b/addons/xterm-addon-webgl/src/GlyphRenderer.ts
index 1c75b3b9..269d9374 100644
--- a/addons/xterm-addon-webgl/src/GlyphRenderer.ts
+++ b/addons/xterm-addon-webgl/src/GlyphRenderer.ts
@@ -11,6 +11,8 @@ import { IRasterizedGlyph, IRenderDimensions, ITextureAtlas } from 'browser/rend
 import { Disposable, toDisposable } from 'common/Lifecycle';
 import { throwIfFalsy } from 'browser/renderer/shared/RendererUtils';
 import { TextureAtlas } from 'browser/renderer/shared/TextureAtlas';
+import { ILogService } from 'common/services/Services';
+import { traceCall } from 'common/services/LogService';
 
 interface IVertices {
   attributes: Float32Array;
@@ -212,6 +214,7 @@ export class GlyphRenderer extends Disposable {
     return this._atlas ? this._atlas.beginFrame() : true;
   }
 
+  @traceCall
   public updateCell(x: number, y: number, code: number, bg: number, fg: number, ext: number, chars: string, lastBg: number): void {
     // Since this function is called for every cell (`rows*cols`), it must be very optimized. It
     // should not instantiate any variables unless a new glyph is drawn to the cache where the
diff --git a/addons/xterm-addon-webgl/src/WebglAddon.ts b/addons/xterm-addon-webgl/src/WebglAddon.ts
index 97e2ce0c..3e091f0b 100644
--- a/addons/xterm-addon-webgl/src/WebglAddon.ts
+++ b/addons/xterm-addon-webgl/src/WebglAddon.ts
@@ -8,9 +8,10 @@ import { ITerminal } from 'browser/Types';
 import { EventEmitter, forwardEvent } from 'common/EventEmitter';
 import { Disposable, toDisposable } from 'common/Lifecycle';
 import { getSafariVersion, isSafari } from 'common/Platform';
-import { ICoreService, IDecorationService, IOptionsService } from 'common/services/Services';
+import { ICoreService, IDecorationService, ILogService, IOptionsService } from 'common/services/Services';
 import { ITerminalAddon, Terminal } from 'xterm';
 import { WebglRenderer } from './WebglRenderer';
+import { setTraceLogger } from 'common/services/LogService';
 
 export class WebglAddon extends Disposable implements ITerminalAddon {
   private _terminal?: Terminal;
@@ -51,8 +52,13 @@ export class WebglAddon extends Disposable implements ITerminalAddon {
     const charSizeService: ICharSizeService = unsafeCore._charSizeService;
     const coreBrowserService: ICoreBrowserService = unsafeCore._coreBrowserService;
     const decorationService: IDecorationService = unsafeCore._decorationService;
+    const logService: ILogService = unsafeCore._logService;
     const themeService: IThemeService = unsafeCore._themeService;
 
+    // Set trace logger just in case it hasn't been yet which could happen when the addon is
+    // bundled separately to the core module
+    setTraceLogger(logService);
+
     this._renderer = this.register(new WebglRenderer(
       terminal,
       characterJoinerService,
diff --git a/addons/xterm-addon-webgl/src/WebglRenderer.ts b/addons/xterm-addon-webgl/src/WebglRenderer.ts
index c21086e2..ae770410 100644
--- a/addons/xterm-addon-webgl/src/WebglRenderer.ts
+++ b/addons/xterm-addon-webgl/src/WebglRenderer.ts
@@ -16,8 +16,8 @@ import { AttributeData } from 'common/buffer/AttributeData';
 import { CellData } from 'common/buffer/CellData';
 import { Attributes, Content, NULL_CELL_CHAR, NULL_CELL_CODE } from 'common/buffer/Constants';
 import { EventEmitter, forwardEvent } from 'common/EventEmitter';
-import { Disposable, getDisposeArrayDisposable, toDisposable } from 'common/Lifecycle';
-import { ICoreService, IDecorationService, IOptionsService } from 'common/services/Services';
+import { Disposable, MutableDisposable, getDisposeArrayDisposable, toDisposable } from 'common/Lifecycle';
+import { ICoreService, IDecorationService, ILogService, IOptionsService } from 'common/services/Services';
 import { CharData, IBufferLine, ICellData } from 'common/Types';
 import { IDisposable, Terminal } from 'xterm';
 import { GlyphRenderer } from './GlyphRenderer';
@@ -27,10 +27,11 @@ import { LinkRenderLayer } from './renderLayer/LinkRenderLayer';
 import { IRenderLayer } from './renderLayer/Types';
 import { COMBINED_CHAR_BIT_MASK, RenderModel, RENDER_MODEL_BG_OFFSET, RENDER_MODEL_EXT_OFFSET, RENDER_MODEL_FG_OFFSET, RENDER_MODEL_INDICIES_PER_CELL } from './RenderModel';
 import { IWebGL2RenderingContext } from './Types';
+import { traceCall } from 'common/services/LogService';
 
 export class WebglRenderer extends Disposable implements IRenderer {
   private _renderLayers: IRenderLayer[];
-  private _cursorBlinkStateManager: CursorBlinkStateManager | undefined;
+  private _cursorBlinkStateManager: MutableDisposable<CursorBlinkStateManager> = new MutableDisposable();
   private _charAtlasDisposable: IDisposable | undefined;
   private _charAtlas: ITextureAtlas | undefined;
   private _devicePixelRatio: number;
@@ -202,7 +203,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     for (const l of this._renderLayers) {
       l.handleBlur(this._terminal);
     }
-    this._cursorBlinkStateManager?.pause();
+    this._cursorBlinkStateManager.value?.pause();
     // Request a redraw for active/inactive selection background
     this._requestRedrawViewport();
   }
@@ -211,7 +212,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     for (const l of this._renderLayers) {
       l.handleFocus(this._terminal);
     }
-    this._cursorBlinkStateManager?.resume();
+    this._cursorBlinkStateManager.value?.resume();
     // Request a redraw for active/inactive selection background
     this._requestRedrawViewport();
   }
@@ -228,7 +229,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     for (const l of this._renderLayers) {
       l.handleCursorMove(this._terminal);
     }
-    this._cursorBlinkStateManager?.restartBlinkAnimation();
+    this._cursorBlinkStateManager.value?.restartBlinkAnimation();
   }
 
   private _handleOptionsChanged(): void {
@@ -311,7 +312,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
       l.reset(this._terminal);
     }
 
-    this._cursorBlinkStateManager?.restartBlinkAnimation();
+    this._cursorBlinkStateManager.value?.restartBlinkAnimation();
     this._updateCursorBlink();
   }
 
@@ -323,6 +324,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     return false;
   }
 
+  @traceCall
   public renderRows(start: number, end: number): void {
     if (!this._isAttached) {
       if (this._coreBrowserService.window.document.body.contains(this._core.screenElement!) && this._charSizeService.width && this._charSizeService.height) {
@@ -357,21 +359,18 @@ export class WebglRenderer extends Disposable implements IRenderer {
     // Render
     this._rectangleRenderer?.renderBackgrounds();
     this._glyphRenderer?.render(this._model);
-    if (!this._cursorBlinkStateManager || this._cursorBlinkStateManager.isCursorVisible) {
+    if (!this._cursorBlinkStateManager.value || this._cursorBlinkStateManager.value.isCursorVisible) {
       this._rectangleRenderer?.renderCursor();
     }
   }
 
   private _updateCursorBlink(): void {
     if (this._terminal.options.cursorBlink) {
-      if (!this._cursorBlinkStateManager) {
-        this._cursorBlinkStateManager = this.register(new CursorBlinkStateManager(() => {
-          this._requestRedrawCursor();
-        }, this._coreBrowserService));
-      }
+      this._cursorBlinkStateManager.value = new CursorBlinkStateManager(() => {
+        this._requestRedrawCursor();
+      }, this._coreBrowserService);
     } else {
-      this._cursorBlinkStateManager?.dispose();
-      this._cursorBlinkStateManager = undefined;
+      this._cursorBlinkStateManager.clear();
     }
     // Request a refresh from the terminal as management of rendering is being
     // moved back to the terminal
@@ -406,7 +405,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     const isCursorVisible =
       this._coreService.isCursorInitialized &&
       !this._coreService.isCursorHidden &&
-      (!this._cursorBlinkStateManager || this._cursorBlinkStateManager.isCursorVisible);
+      (!this._cursorBlinkStateManager.value || this._cursorBlinkStateManager.value.isCursorVisible);
     this._model.cursor = undefined;
     let modelUpdated = false;
 
diff --git a/addons/xterm-addon-webgl/src/tsconfig.json b/addons/xterm-addon-webgl/src/tsconfig.json
index f752dc5b..74989973 100644
--- a/addons/xterm-addon-webgl/src/tsconfig.json
+++ b/addons/xterm-addon-webgl/src/tsconfig.json
@@ -21,6 +21,7 @@
     },
     "strict": true,
     "downlevelIteration": true,
+    "experimentalDecorators": true,
     "types": [
       "../../../node_modules/@types/mocha"
     ]
diff --git a/demo/client.ts b/demo/client.ts
index ce6a5c64..7c586528 100644
--- a/demo/client.ts
+++ b/demo/client.ts
@@ -433,7 +433,7 @@ function initOptions(term: TerminalType): void {
     fontFamily: null,
     fontWeight: ['normal', 'bold', '100', '200', '300', '400', '500', '600', '700', '800', '900'],
     fontWeightBold: ['normal', 'bold', '100', '200', '300', '400', '500', '600', '700', '800', '900'],
-    logLevel: ['debug', 'info', 'warn', 'error', 'off'],
+    logLevel: ['trace', 'debug', 'info', 'warn', 'error', 'off'],
     theme: ['default', 'xtermjs', 'sapphire', 'light'],
     wordSeparator: null
   };
diff --git a/src/browser/renderer/shared/TextureAtlas.ts b/src/browser/renderer/shared/TextureAtlas.ts
index eec560e0..3ee21519 100644
--- a/src/browser/renderer/shared/TextureAtlas.ts
+++ b/src/browser/renderer/shared/TextureAtlas.ts
@@ -16,6 +16,7 @@ import { IdleTaskQueue } from 'common/TaskQueue';
 import { IBoundingBox, ICharAtlasConfig, IRasterizedGlyph, IRequestRedrawEvent, ITextureAtlas } from 'browser/renderer/shared/Types';
 import { EventEmitter } from 'common/EventEmitter';
 import { IColorContrastCache } from 'browser/Types';
+import { traceCall } from 'common/services/LogService';
 
 /**
  * A shared object which is used to draw nothing for a particular cell.
@@ -425,6 +426,7 @@ export class TextureAtlas implements ITextureAtlas {
     return this._config.colors.contrastCache;
   }
 
+  @traceCall
   private _drawToCache(codeOrChars: number | string, bg: number, fg: number, ext: number, restrictToCellHeight: boolean = false): IRasterizedGlyph {
     const chars = typeof codeOrChars === 'number' ? String.fromCharCode(codeOrChars) : codeOrChars;
 
diff --git a/src/common/Lifecycle.test.ts b/src/common/Lifecycle.test.ts
index 6f7c7884..8f8a4932 100644
--- a/src/common/Lifecycle.test.ts
+++ b/src/common/Lifecycle.test.ts
@@ -4,7 +4,8 @@
  */
 
 import { assert } from 'chai';
-import { Disposable } from 'common/Lifecycle';
+import { Disposable, MutableDisposable } from 'common/Lifecycle';
+import { IDisposable } from 'common/Types';
 
 class TestDisposable extends Disposable {
   public get isDisposed(): boolean {
@@ -43,3 +44,52 @@ describe('Disposable', () => {
     });
   });
 });
+
+describe('MutableDisposable', () => {
+  const mutable = new MutableDisposable();
+  class TrackedDisposable extends Disposable {
+    public get isDisposed(): boolean { return this._isDisposed; }
+  }
+  describe('value', () => {
+    it('should set the value', () => {
+      const d1 = new TrackedDisposable();
+      mutable.value = d1;
+      assert.strictEqual(mutable.value, d1);
+      assert.isFalse(d1.isDisposed);
+    });
+    it('should dispose of any previous value', () => {
+      const d1 = new TrackedDisposable();
+      const d2 = new TrackedDisposable();
+      mutable.value = d1;
+      mutable.value = d2;
+      assert.strictEqual(mutable.value, d2);
+      assert.isTrue(d1.isDisposed);
+      assert.isFalse(d2.isDisposed);
+    });
+  });
+  describe('clear', () => {
+    it('should clear and dispose of the object', () => {
+      const d1 = new TrackedDisposable();
+      mutable.value = d1;
+      mutable.clear();
+      assert.strictEqual(mutable.value, undefined);
+      assert.isTrue(d1.isDisposed);
+    });
+  });
+  it('dispose', () => {
+    it('should dispose of the object', () => {
+      const d1 = new TrackedDisposable();
+      mutable.value = d1;
+      mutable.dispose();
+      assert.strictEqual(mutable.value, undefined);
+      assert.isTrue(d1.isDisposed);
+    });
+    it('should prevent using the MutableDisposable again', () => {
+      const d1 = new TrackedDisposable();
+      mutable.value = d1;
+      mutable.dispose();
+      mutable.value = new TrackedDisposable();
+      assert.strictEqual(mutable.value, undefined);
+    });
+  });
+});
diff --git a/src/common/Lifecycle.ts b/src/common/Lifecycle.ts
index b3a7cc21..659403de 100644
--- a/src/common/Lifecycle.ts
+++ b/src/common/Lifecycle.ts
@@ -50,6 +50,42 @@ export abstract class Disposable implements IDisposable {
   }
 }
 
+export class MutableDisposable<T extends IDisposable> implements IDisposable {
+  private _value?: T;
+  private _isDisposed = false;
+
+  /**
+   * Gets the value if it exists.
+   */
+  public get value(): T | undefined {
+    return this._isDisposed ? undefined : this._value;
+  }
+
+  /**
+   * Sets the value, disposing of the old value if it exists.
+   */
+  public set value(value: T | undefined) {
+    if (this._isDisposed || value === this._value) {
+      return;
+    }
+    this._value?.dispose();
+    this._value = value;
+  }
+
+  /**
+   * Resets the stored value and disposes of the previously stored value.
+   */
+  public clear(): void {
+    this.value = undefined;
+  }
+
+  public dispose(): void {
+    this._isDisposed = true;
+    this._value?.dispose();
+    this._value = undefined;
+  }
+}
+
 /**
  * Wrap a function in a disposable.
  */
diff --git a/src/common/TestUtils.test.ts b/src/common/TestUtils.test.ts
index ceb0dc29..fcf0c2cd 100644
--- a/src/common/TestUtils.test.ts
+++ b/src/common/TestUtils.test.ts
@@ -105,6 +105,7 @@ export class MockCoreService implements ICoreService {
 export class MockLogService implements ILogService {
   public serviceBrand: any;
   public logLevel = LogLevelEnum.DEBUG;
+  public trace(message: any, ...optionalParams: any[]): void { }
   public debug(message: any, ...optionalParams: any[]): void { }
   public info(message: any, ...optionalParams: any[]): void { }
   public warn(message: any, ...optionalParams: any[]): void { }
diff --git a/src/common/services/LogService.ts b/src/common/services/LogService.ts
index b297049e..b3a7450c 100644
--- a/src/common/services/LogService.ts
+++ b/src/common/services/LogService.ts
@@ -21,6 +21,7 @@ interface IConsole {
 declare const console: IConsole;
 
 const optionsKeyToLogLevel: { [key: string]: LogLevelEnum } = {
+  trace: LogLevelEnum.TRACE,
   debug: LogLevelEnum.DEBUG,
   info: LogLevelEnum.INFO,
   warn: LogLevelEnum.WARN,
@@ -42,6 +43,9 @@ export class LogService extends Disposable implements ILogService {
     super();
     this._updateLogLevel();
     this.register(this._optionsService.onSpecificOptionChange('logLevel', () => this._updateLogLevel()));
+
+    // For trace logging, assume the latest created log service is valid
+    traceLogger = this;
   }
 
   private _updateLogLevel(): void {
@@ -61,6 +65,12 @@ export class LogService extends Disposable implements ILogService {
     type.call(console, (this._optionsService.options.logger ? '' : LOG_PREFIX) + message, ...optionalParams);
   }
 
+  public trace(message: string, ...optionalParams: any[]): void {
+    if (this._logLevel <= LogLevelEnum.TRACE) {
+      this._log(this._optionsService.options.logger?.trace.bind(this._optionsService.options.logger) ?? console.log, message, optionalParams);
+    }
+  }
+
   public debug(message: string, ...optionalParams: any[]): void {
     if (this._logLevel <= LogLevelEnum.DEBUG) {
       this._log(this._optionsService.options.logger?.debug.bind(this._optionsService.options.logger) ?? console.log, message, optionalParams);
@@ -85,3 +95,30 @@ export class LogService extends Disposable implements ILogService {
     }
   }
 }
+
+let traceLogger: ILogService;
+export function setTraceLogger(logger: ILogService): void {
+  traceLogger = logger;
+}
+
+/**
+ * A decorator that can be used to automatically log trace calls to the decorated function.
+ */
+export function traceCall(_target: any, key: string, descriptor: any): any {
+  if (typeof descriptor.value !== 'function') {
+    throw new Error('not supported');
+  }
+  const fnKey = 'value';
+  const fn = descriptor.value;
+  descriptor[fnKey] = function (...args: any[]) {
+    // Early exit
+    if (traceLogger.logLevel !== LogLevelEnum.TRACE) {
+      return fn.apply(this, args);
+    }
+
+    traceLogger.trace(`GlyphRenderer#${fn.name}(${args.map(e => JSON.stringify(e)).join(', ')})`);
+    const result = fn.apply(this, args);
+    traceLogger.trace(`GlyphRenderer#${fn.name} return`, result);
+    return result;
+  };
+}
diff --git a/src/common/services/Services.ts b/src/common/services/Services.ts
index 625fc7de..52c2a79f 100644
--- a/src/common/services/Services.ts
+++ b/src/common/services/Services.ts
@@ -142,11 +142,12 @@ export interface IInstantiationService {
 }
 
 export enum LogLevelEnum {
-  DEBUG = 0,
-  INFO = 1,
-  WARN = 2,
-  ERROR = 3,
-  OFF = 4
+  TRACE = 0,
+  DEBUG = 1,
+  INFO = 2,
+  WARN = 3,
+  ERROR = 4,
+  OFF = 5
 }
 
 export const ILogService = createDecorator<ILogService>('LogService');
@@ -155,6 +156,7 @@ export interface ILogService {
 
   readonly logLevel: LogLevelEnum;
 
+  trace(message: any, ...optionalParams: any[]): void;
   debug(message: any, ...optionalParams: any[]): void;
   info(message: any, ...optionalParams: any[]): void;
   warn(message: any, ...optionalParams: any[]): void;
@@ -201,7 +203,7 @@ export interface IOptionsService {
 }
 
 export type FontWeight = 'normal' | 'bold' | '100' | '200' | '300' | '400' | '500' | '600' | '700' | '800' | '900' | number;
-export type LogLevel = 'debug' | 'info' | 'warn' | 'error' | 'off';
+export type LogLevel = 'trace' | 'debug' | 'info' | 'warn' | 'error' | 'off';
 
 export interface ITerminalOptions {
   allowProposedApi?: boolean;
diff --git a/typings/xterm-headless.d.ts b/typings/xterm-headless.d.ts
index 118c5905..99aa8237 100644
--- a/typings/xterm-headless.d.ts
+++ b/typings/xterm-headless.d.ts
@@ -11,7 +11,7 @@ declare module 'xterm-headless' {
   /**
    * A string representing log level.
    */
-  export type LogLevel = 'debug' | 'info' | 'warn' | 'error' | 'off';
+  export type LogLevel = 'trace' | 'debug' | 'info' | 'warn' | 'error' | 'off';
 
   /**
    * An object containing options for the terminal.
@@ -100,11 +100,12 @@ declare module 'xterm-headless' {
      * What log level to use, this will log for all levels below and including
      * what is set:
      *
-     * 1. debug
-     * 2. info (default)
-     * 3. warn
-     * 4. error
-     * 5. off
+     * 1. trace
+     * 2. debug
+     * 3. info (default)
+     * 4. warn
+     * 5. error
+     * 6. off
      */
     logLevel?: LogLevel;
 
@@ -314,9 +315,14 @@ declare module 'xterm-headless' {
    * A replacement logger for `console`.
    */
   export interface ILogger {
+    /**
+     * Log a trace message, this will only be called if
+     * {@link ITerminalOptions.logLevel} is set to trace.
+     */
+    trace(message: string, ...args: any[]): void;
     /**
      * Log a debug message, this will only be called if
-     * {@link ITerminalOptions.logLevel} is set to debug.
+     * {@link ITerminalOptions.logLevel} is set to debug or below.
      */
     debug(message: string, ...args: any[]): void;
     /**
diff --git a/typings/xterm.d.ts b/typings/xterm.d.ts
index d7c5e320..3f603b9e 100644
--- a/typings/xterm.d.ts
+++ b/typings/xterm.d.ts
@@ -18,7 +18,7 @@ declare module 'xterm' {
   /**
    * A string representing log level.
    */
-  export type LogLevel = 'debug' | 'info' | 'warn' | 'error' | 'off';
+  export type LogLevel = 'trace' | 'debug' | 'info' | 'warn' | 'error' | 'off';
 
   /**
    * An object containing options for the terminal.
@@ -158,11 +158,12 @@ declare module 'xterm' {
      * What log level to use, this will log for all levels below and including
      * what is set:
      *
-     * 1. debug
-     * 2. info (default)
-     * 3. warn
-     * 4. error
-     * 5. off
+     * 1. trace
+     * 2. debug
+     * 3. info (default)
+     * 4. warn
+     * 5. error
+     * 6. off
      */
     logLevel?: LogLevel;
 
@@ -391,9 +392,14 @@ declare module 'xterm' {
    * A replacement logger for `console`.
    */
   export interface ILogger {
+    /**
+     * Log a trace message, this will only be called if
+     * {@link ITerminalOptions.logLevel} is set to trace.
+     */
+    trace(message: string, ...args: any[]): void;
     /**
      * Log a debug message, this will only be called if
-     * {@link ITerminalOptions.logLevel} is set to debug.
+     * {@link ITerminalOptions.logLevel} is set to debug or below.
      */
     debug(message: string, ...args: any[]): void;
     /**