diff --git a/src/common/InputHandler.ts b/src/common/InputHandler.ts
index 7ab2a186..a35f7981 100644
--- a/src/common/InputHandler.ts
+++ b/src/common/InputHandler.ts
@@ -4,7 +4,7 @@
  * @license MIT
  */
 
-import { IInputHandler, IAttributeData, IDisposable, IWindowOptions, IAnsiColorChangeEvent } from 'common/Types';
+import { IInputHandler, IAttributeData, IDisposable, IWindowOptions, IAnsiColorChangeEvent, IParseStack } from 'common/Types';
 import { C0, C1 } from 'common/data/EscapeSequences';
 import { CHARSETS, DEFAULT_CHARSET } from 'common/data/Charsets';
 import { EscapeSequenceParser } from 'common/parser/EscapeSequenceParser';
@@ -17,10 +17,9 @@ import { IParsingState, IDcsHandler, IEscapeSequenceParser, IParams, IFunctionId
 import { NULL_CELL_CODE, NULL_CELL_WIDTH, Attributes, FgFlags, BgFlags, Content, UnderlineStyle } from 'common/buffer/Constants';
 import { CellData } from 'common/buffer/CellData';
 import { AttributeData } from 'common/buffer/AttributeData';
-import { ICoreService, IBufferService, IOptionsService, ILogService, IDirtyRowService, ICoreMouseService, ICharsetService, IUnicodeService } from 'common/services/Services';
+import { ICoreService, IBufferService, IOptionsService, ILogService, IDirtyRowService, ICoreMouseService, ICharsetService, IUnicodeService, LogLevelEnum } from 'common/services/Services';
 import { OscHandler } from 'common/parser/OscParser';
 import { DcsHandler } from 'common/parser/DcsParser';
-import { LogLevel } from 'common/services/LogService';
 
 /**
  * Map collect to glevel. Used in `selectCharset`.
@@ -263,6 +262,14 @@ export class InputHandler extends Disposable implements IInputHandler {
   private _onAnsiColorChange = new EventEmitter<IAnsiColorChangeEvent>();
   public get onAnsiColorChange(): IEvent<IAnsiColorChangeEvent> { return this._onAnsiColorChange.event; }
 
+  private _parseStack: IParseStack = {
+    paused: false,
+    cursorStartX: 0,
+    cursorStartY: 0,
+    decodedLength: 0,
+    position: 0
+  };
+
   constructor(
     private readonly _bufferService: IBufferService,
     private readonly _charsetService: ICharsetService,
@@ -467,13 +474,6 @@ export class InputHandler extends Disposable implements IInputHandler {
   /**
    * Async parse support.
    */
-  private _parseStack = {
-    paused: false,
-    cursorStartX: 0,
-    cursorStartY: 0,
-    decodedLength: 0,
-    position: 0
-  };
   private _preserveStack(cursorStartX: number, cursorStartY: number, decodedLength: number, position: number): void {
     this._parseStack.paused = true;
     this._parseStack.cursorStartX = cursorStartX;
@@ -481,9 +481,10 @@ export class InputHandler extends Disposable implements IInputHandler {
     this._parseStack.decodedLength = decodedLength;
     this._parseStack.position = position;
   }
+
   private _logSlowResolvingAsync(p: Promise<boolean>): void {
-    // log a limited warning about an async taking too long
-    if ((this._logService as any)._logLevel <= LogLevel.WARN) {
+    // log a limited warning about an async handler taking too long
+    if (this._logService.logLevel <= LogLevelEnum.WARN) {
       Promise.race([p, new Promise((res, rej) => setTimeout(() => rej('#SLOW_TIMEOUT'), SLOW_ASYNC_LIMIT))])
         .catch(err => {
           if (err !== '#SLOW_TIMEOUT') {
diff --git a/src/common/TestUtils.test.ts b/src/common/TestUtils.test.ts
index 35357744..01ceacbd 100644
--- a/src/common/TestUtils.test.ts
+++ b/src/common/TestUtils.test.ts
@@ -3,7 +3,7 @@
  * @license MIT
  */
 
-import { IBufferService, ICoreService, ILogService, IOptionsService, ITerminalOptions, IPartialTerminalOptions, IDirtyRowService, ICoreMouseService, ICharsetService, IUnicodeService, IUnicodeVersionProvider } from 'common/services/Services';
+import { IBufferService, ICoreService, ILogService, IOptionsService, ITerminalOptions, IPartialTerminalOptions, IDirtyRowService, ICoreMouseService, ICharsetService, IUnicodeService, IUnicodeVersionProvider, LogLevelEnum } from 'common/services/Services';
 import { IEvent, EventEmitter } from 'common/EventEmitter';
 import { clone } from 'common/Clone';
 import { DEFAULT_OPTIONS } from 'common/services/OptionsService';
@@ -92,6 +92,7 @@ export class MockDirtyRowService implements IDirtyRowService {
 
 export class MockLogService implements ILogService {
   public serviceBrand: any;
+  public logLevel = LogLevelEnum.DEBUG;
   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/Types.d.ts b/src/common/Types.d.ts
index e345e11d..108d81ac 100644
--- a/src/common/Types.d.ts
+++ b/src/common/Types.d.ts
@@ -349,7 +349,7 @@ export interface IInputHandler {
   onTitleChange: IEvent<string>;
   onRequestScroll: IEvent<IAttributeData, boolean | void>;
 
-  parse(data: string | Uint8Array): void;
+  parse(data: string | Uint8Array, promiseResult?: boolean): void | Promise<boolean>;
   print(data: Uint32Array, start: number, end: number): void;
   registerCsiHandler(id: IFunctionIdentifier, callback: (params: IParams) => boolean | Promise<boolean>): IDisposable;
   registerDcsHandler(id: IFunctionIdentifier, callback: (data: string, param: IParams) => boolean | Promise<boolean>): IDisposable;
@@ -431,3 +431,11 @@ export interface IInputHandler {
       ESC ~ */ setgLevel(level: number): void;
   /** ESC # 8 */ screenAlignmentPattern(): void;
 }
+
+interface IParseStack {
+  paused: boolean;
+  cursorStartX: number;
+  cursorStartY: number;
+  decodedLength: number;
+  position: number;
+}
diff --git a/src/common/services/LogService.ts b/src/common/services/LogService.ts
index 3c0ccaf1..de4e18f8 100644
--- a/src/common/services/LogService.ts
+++ b/src/common/services/LogService.ts
@@ -3,7 +3,7 @@
  * @license MIT
  */
 
-import { ILogService, IOptionsService } from 'common/services/Services';
+import { ILogService, IOptionsService, LogLevelEnum } from 'common/services/Services';
 
 type LogType = (message?: any, ...optionalParams: any[]) => void;
 
@@ -19,21 +19,12 @@ interface IConsole {
 // module doesn't depend on them so we need to explicitly declare it.
 declare const console: IConsole;
 
-
-export enum LogLevel {
-  DEBUG = 0,
-  INFO = 1,
-  WARN = 2,
-  ERROR = 3,
-  OFF = 4
-}
-
-const optionsKeyToLogLevel: { [key: string]: LogLevel } = {
-  debug: LogLevel.DEBUG,
-  info: LogLevel.INFO,
-  warn: LogLevel.WARN,
-  error: LogLevel.ERROR,
-  off: LogLevel.OFF
+const optionsKeyToLogLevel: { [key: string]: LogLevelEnum } = {
+  debug: LogLevelEnum.DEBUG,
+  info: LogLevelEnum.INFO,
+  warn: LogLevelEnum.WARN,
+  error: LogLevelEnum.ERROR,
+  off: LogLevelEnum.OFF
 };
 
 const LOG_PREFIX = 'xterm.js: ';
@@ -41,7 +32,7 @@ const LOG_PREFIX = 'xterm.js: ';
 export class LogService implements ILogService {
   public serviceBrand: any;
 
-  private _logLevel!: LogLevel;
+  public logLevel: LogLevelEnum = LogLevelEnum.OFF;
 
   constructor(
     @IOptionsService private readonly _optionsService: IOptionsService
@@ -55,7 +46,7 @@ export class LogService implements ILogService {
   }
 
   private _updateLogLevel(): void {
-    this._logLevel = optionsKeyToLogLevel[this._optionsService.options.logLevel];
+    this.logLevel = optionsKeyToLogLevel[this._optionsService.options.logLevel];
   }
 
   private _evalLazyOptionalParams(optionalParams: any[]): void {
@@ -72,25 +63,25 @@ export class LogService implements ILogService {
   }
 
   public debug(message: string, ...optionalParams: any[]): void {
-    if (this._logLevel <= LogLevel.DEBUG) {
+    if (this.logLevel <= LogLevelEnum.DEBUG) {
       this._log(console.log, message, optionalParams);
     }
   }
 
   public info(message: string, ...optionalParams: any[]): void {
-    if (this._logLevel <= LogLevel.INFO) {
+    if (this.logLevel <= LogLevelEnum.INFO) {
       this._log(console.info, message, optionalParams);
     }
   }
 
   public warn(message: string, ...optionalParams: any[]): void {
-    if (this._logLevel <= LogLevel.WARN) {
+    if (this.logLevel <= LogLevelEnum.WARN) {
       this._log(console.warn, message, optionalParams);
     }
   }
 
   public error(message: string, ...optionalParams: any[]): void {
-    if (this._logLevel <= LogLevel.ERROR) {
+    if (this.logLevel <= LogLevelEnum.ERROR) {
       this._log(console.error, message, optionalParams);
     }
   }
diff --git a/src/common/services/Services.ts b/src/common/services/Services.ts
index c733e73e..1fbf57fb 100644
--- a/src/common/services/Services.ts
+++ b/src/common/services/Services.ts
@@ -161,6 +161,8 @@ export const ILogService = createDecorator<ILogService>('LogService');
 export interface ILogService {
   serviceBrand: undefined;
 
+  logLevel: LogLevelEnum;
+
   debug(message: any, ...optionalParams: any[]): void;
   info(message: any, ...optionalParams: any[]): void;
   warn(message: any, ...optionalParams: any[]): void;
@@ -181,6 +183,13 @@ 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 enum LogLevelEnum {
+  DEBUG = 0,
+  INFO = 1,
+  WARN = 2,
+  ERROR = 3,
+  OFF = 4
+}
 export type RendererType = 'dom' | 'canvas';
 
 export interface IPartialTerminalOptions {