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diff --git a/node_modules/xterm/src/common/input/WriteBuffer.ts b/node_modules/xterm/src/common/input/WriteBuffer.ts
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+++ b/node_modules/xterm/src/common/input/WriteBuffer.ts
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+
+/**
+ * Copyright (c) 2019 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+declare const setTimeout: (handler: () => void, timeout?: number) => void;
+
+/**
+ * Safety watermark to avoid memory exhaustion and browser engine crash on fast data input.
+ * Enable flow control to avoid this limit and make sure that your backend correctly
+ * propagates this to the underlying pty. (see docs for further instructions)
+ * Since this limit is meant as a safety parachute to prevent browser crashs,
+ * it is set to a very high number. Typically xterm.js gets unresponsive with
+ * a 100 times lower number (>500 kB).
+ */
+const DISCARD_WATERMARK = 50000000; // ~50 MB
+
+/**
+ * The max number of ms to spend on writes before allowing the renderer to
+ * catch up with a 0ms setTimeout. A value of < 33 to keep us close to
+ * 30fps, and a value of < 16 to try to run at 60fps. Of course, the real FPS
+ * depends on the time it takes for the renderer to draw the frame.
+ */
+const WRITE_TIMEOUT_MS = 12;
+
+/**
+ * Threshold of max held chunks in the write buffer, that were already processed.
+ * This is a tradeoff between extensive write buffer shifts (bad runtime) and high
+ * memory consumption by data thats not used anymore.
+ */
+const WRITE_BUFFER_LENGTH_THRESHOLD = 50;
+
+// queueMicrotask polyfill for nodejs < v11
+const qmt: (cb: () => void) => void = (typeof queueMicrotask === 'undefined')
+  ? (cb: () => void) => { Promise.resolve().then(cb); }
+  : queueMicrotask;
+
+
+export class WriteBuffer {
+  private _writeBuffer: (string | Uint8Array)[] = [];
+  private _callbacks: ((() => void) | undefined)[] = [];
+  private _pendingData = 0;
+  private _bufferOffset = 0;
+  private _isSyncWriting = false;
+  private _syncCalls = 0;
+
+  constructor(private _action: (data: string | Uint8Array, promiseResult?: boolean) => void | Promise<boolean>) { }
+
+  /**
+   * @deprecated Unreliable, to be removed soon.
+   */
+  public writeSync(data: string | Uint8Array, maxSubsequentCalls?: number): void {
+    // stop writeSync recursions with maxSubsequentCalls argument
+    // This is dangerous to use as it will lose the current data chunk
+    // and return immediately.
+    if (maxSubsequentCalls !== undefined && this._syncCalls > maxSubsequentCalls) {
+      // comment next line if a whole loop block should only contain x `writeSync` calls
+      // (total flat vs. deep nested limit)
+      this._syncCalls = 0;
+      return;
+    }
+    // append chunk to buffer
+    this._pendingData += data.length;
+    this._writeBuffer.push(data);
+    this._callbacks.push(undefined);
+
+    // increase recursion counter
+    this._syncCalls++;
+    // exit early if another writeSync loop is active
+    if (this._isSyncWriting) {
+      return;
+    }
+    this._isSyncWriting = true;
+
+    // force sync processing on pending data chunks to avoid in-band data scrambling
+    // does the same as innerWrite but without event loop
+    // we have to do it here as single loop steps to not corrupt loop subject
+    // by another writeSync call triggered from _action
+    let chunk: string | Uint8Array | undefined;
+    while (chunk = this._writeBuffer.shift()) {
+      this._action(chunk);
+      const cb = this._callbacks.shift();
+      if (cb) cb();
+    }
+    // reset to avoid reprocessing of chunks with scheduled innerWrite call
+    // stopping scheduled innerWrite by offset > length condition
+    this._pendingData = 0;
+    this._bufferOffset = 0x7FFFFFFF;
+
+    // allow another writeSync to loop
+    this._isSyncWriting = false;
+    this._syncCalls = 0;
+  }
+
+  public write(data: string | Uint8Array, callback?: () => void): void {
+    if (this._pendingData > DISCARD_WATERMARK) {
+      throw new Error('write data discarded, use flow control to avoid losing data');
+    }
+
+    // schedule chunk processing for next event loop run
+    if (!this._writeBuffer.length) {
+      this._bufferOffset = 0;
+      setTimeout(() => this._innerWrite());
+    }
+
+    this._pendingData += data.length;
+    this._writeBuffer.push(data);
+    this._callbacks.push(callback);
+  }
+
+  /**
+   * Inner write call, that enters the sliced chunk processing by timing.
+   *
+   * `lastTime` indicates, when the last _innerWrite call had started.
+   * It is used to aggregate async handler execution under a timeout constraint
+   * effectively lowering the redrawing needs, schematically:
+   *
+   *   macroTask _innerWrite:
+   *     if (Date.now() - (lastTime | 0) < WRITE_TIMEOUT_MS):
+   *        schedule microTask _innerWrite(lastTime)
+   *     else:
+   *        schedule macroTask _innerWrite(0)
+   *
+   *   overall execution order on task queues:
+   *
+   *   macrotasks:  [...]  -->  _innerWrite(0)  -->  [...]  -->  screenUpdate  -->  [...]
+   *         m  t:                    |
+   *         i  a:                  [...]
+   *         c  s:                    |
+   *         r  k:              while < timeout:
+   *         o  s:                _innerWrite(timeout)
+   *
+   * `promiseResult` depicts the promise resolve value of an async handler.
+   * This value gets carried forward through all saved stack states of the
+   * paused parser for proper continuation.
+   *
+   * Note, for pure sync code `lastTime` and `promiseResult` have no meaning.
+   */
+  protected _innerWrite(lastTime: number = 0, promiseResult: boolean = true): void {
+    const startTime = lastTime || Date.now();
+    while (this._writeBuffer.length > this._bufferOffset) {
+      const data = this._writeBuffer[this._bufferOffset];
+      const result = this._action(data, promiseResult);
+      if (result) {
+        /**
+         * If we get a promise as return value, we re-schedule the continuation
+         * as thenable on the promise and exit right away.
+         *
+         * The exit here means, that we block input processing at the current active chunk,
+         * the exact execution position within the chunk is preserved by the saved
+         * stack content in InputHandler and EscapeSequenceParser.
+         *
+         * Resuming happens automatically from that saved stack state.
+         * Also the resolved promise value is passed along the callstack to
+         * `EscapeSequenceParser.parse` to correctly resume the stopped handler loop.
+         *
+         * Exceptions on async handlers will be logged to console async, but do not interrupt
+         * the input processing (continues with next handler at the current input position).
+         */
+
+        /**
+         * If a promise takes long to resolve, we should schedule continuation behind setTimeout.
+         * This might already be too late, if our .then enters really late (executor + prev thens took very long).
+         * This cannot be solved here for the handler itself (it is the handlers responsibility to slice hard work),
+         * but we can at least schedule a screen update as we gain control.
+         */
+        const continuation: (r: boolean) => void = (r: boolean) => Date.now() - startTime >= WRITE_TIMEOUT_MS
+          ? setTimeout(() => this._innerWrite(0, r))
+          : this._innerWrite(startTime, r);
+
+        /**
+         * Optimization considerations:
+         * The continuation above favors FPS over throughput by eval'ing `startTime` on resolve.
+         * This might schedule too many screen updates with bad throughput drops (in case a slow
+         * resolving handler sliced its work properly behind setTimeout calls). We cannot spot
+         * this condition here, also the renderer has no way to spot nonsense updates either.
+         * FIXME: A proper fix for this would track the FPS at the renderer entry level separately.
+         *
+         * If favoring of FPS shows bad throughtput impact, use the following instead. It favors
+         * throughput by eval'ing `startTime` upfront pulling at least one more chunk into the
+         * current microtask queue (executed before setTimeout).
+         */
+        // const continuation: (r: boolean) => void = Date.now() - startTime >= WRITE_TIMEOUT_MS
+        //   ? r => setTimeout(() => this._innerWrite(0, r))
+        //   : r => this._innerWrite(startTime, r);
+
+        // Handle exceptions synchronously to current band position, idea:
+        // 1. spawn a single microtask which we allow to throw hard
+        // 2. spawn a promise immediately resolving to `true`
+        // (executed on the same queue, thus properly aligned before continuation happens)
+        result.catch(err => {
+          qmt(() => {throw err;});
+          return Promise.resolve(false);
+        }).then(continuation);
+        return;
+      }
+
+      const cb = this._callbacks[this._bufferOffset];
+      if (cb) cb();
+      this._bufferOffset++;
+      this._pendingData -= data.length;
+
+      if (Date.now() - startTime >= WRITE_TIMEOUT_MS) {
+        break;
+      }
+    }
+    if (this._writeBuffer.length > this._bufferOffset) {
+      // Allow renderer to catch up before processing the next batch
+      // trim already processed chunks if we are above threshold
+      if (this._bufferOffset > WRITE_BUFFER_LENGTH_THRESHOLD) {
+        this._writeBuffer = this._writeBuffer.slice(this._bufferOffset);
+        this._callbacks = this._callbacks.slice(this._bufferOffset);
+        this._bufferOffset = 0;
+      }
+      setTimeout(() => this._innerWrite());
+    } else {
+      this._writeBuffer.length = 0;
+      this._callbacks.length = 0;
+      this._pendingData = 0;
+      this._bufferOffset = 0;
+    }
+  }
+}