Add bash script demonstrating browser shell-wrapper pipe-hang bug (Brave + Chromium)

.devcontainer/Dockerfile

@@ -0,0 +1,73 @@
+FROM node:22-bookworm-slim
+
+# Avoid interactive prompts during package installation
+ENV DEBIAN_FRONTEND=noninteractive
+
+# Install basic tools, Brave browser runtime dependencies, and git
+RUN apt-get update && apt-get install -y \
+    ca-certificates \
+    curl \
+    fonts-liberation \
+    git \
+    libasound2 \
+    libatk-bridge2.0-0 \
+    libatk1.0-0 \
+    libatspi2.0-0 \
+    libcairo2 \
+    libcups2 \
+    libcurl4 \
+    libdbus-1-3 \
+    libexpat1 \
+    libgbm1 \
+    libglib2.0-0 \
+    libgtk-3-0 \
+    libnspr4 \
+    libnss3 \
+    libpango-1.0-0 \
+    libudev1 \
+    libvulkan1 \
+    libx11-6 \
+    libxcb1 \
+    libxcomposite1 \
+    libxdamage1 \
+    libxext6 \
+    libxfixes3 \
+    libxkbcommon0 \
+    libxrandr2 \
+    sudo \
+    wget \
+    xdg-utils \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Brave Browser from the official Brave APT repository.
+# brave-keyring is not needed for browser operation so it is excluded.
+RUN curl -fsSLo /usr/share/keyrings/brave-browser-archive-keyring.gpg \
+        https://brave-browser-apt-release.s3.brave.com/brave-browser-archive-keyring.gpg \
+    && echo "deb [signed-by=/usr/share/keyrings/brave-browser-archive-keyring.gpg arch=amd64] \
+        https://brave-browser-apt-release.s3.brave.com/ stable main" \
+        > /etc/apt/sources.list.d/brave-browser-release.list \
+    && apt-get update \
+    && apt-get install -y --no-install-recommends brave-browser \
+    && rm -rf /var/lib/apt/lists/*
+
+# Create a non-root user (vscode is the standard devcontainer user name).
+# The node:22 base image already has a 'node' user; create 'vscode' following
+# devcontainer conventions.
+RUN useradd -ms /bin/bash vscode \
+    && echo "vscode ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers
+
+# Point CHROMIUM_BIN at the actual Brave binary, not the /usr/bin/brave-browser
+# shell wrapper.  The wrapper uses bash process-substitutions (exec > >(exec cat))
+# that create cat helper processes inheriting Node.js pipe file descriptors.
+# Because Brave's renderer and crashpad children daemonize (PPID=1), those cat
+# processes keep running after the browser exits and hold Node.js's stdout/stderr
+# pipes open.  Node.js then waits ~40 s for them to exit before it can exit
+# itself, which causes the karma test run to hit the `timeout 180` limit.
+# Pointing directly at the binary avoids the shell wrapper entirely: the brave
+# binary is careful to set FD_CLOEXEC on pipes before it launches child
+# processes, so no child inherits the pipe and Node.js exits immediately after
+# karma finishes.  --no-sandbox is already configured in karma.conf.js.
+ENV CHROMIUM_BIN=/opt/brave.com/brave/brave
+
+USER vscode
+WORKDIR /workspaces/web-xforge