Trying to get software OpenGL rendering to work

.devcontainer/Dockerfile

@@ -1,9 +1,47 @@
 FROM mcr.microsoft.com/devcontainers/base:ubuntu
 
 RUN apt update
-RUN apt install --yes xfce4 xfce4-goodies gnome-icon-theme dbus-x11 xfce4-terminal tightvncserver
+
+# Set non-interactive mode to avoid prompts
+ENV DEBIAN_FRONTEND=noninteractive
+
+# Update the package list and install necessary packages
+RUN apt-get update && \
+    apt-get install -y \
+    mesa-utils \
+    mesa-utils-extra \
+    software-properties-common \
+    build-essential \
+    wget \
+    libx11-dev \
+    libxext-dev \
+    libxdamage-dev \
+    libxfixes-dev \
+    libvulkan-dev \
+    libdrm-dev \
+    libgbm-dev \
+    llvm-dev \
+    llvm
+
+# Install Mesa with software rendering (LLVMPipe)
+RUN add-apt-repository -y ppa:kisak/kisak-mesa && \
+    apt-get update && \
+    apt-get install -y \
+    mesa-opencl-icd \
+    libgl1-mesa-dri
+
+# Set environment variables to use LLVMPipe
+ENV LIBGL_ALWAYS_SOFTWARE=1
+ENV MESA_LOADER_DRIVER_OVERRIDE=llvmpipe
+
+RUN apt install --yes xfce4 xfce4-goodies gnome-icon-theme dbus-x11 xfce4-terminal xvfb x11vnc
 # Register xfce4-terminal as an alternative for x-terminal-emulator
 RUN update-alternatives --install /usr/bin/x-terminal-emulator x-terminal-emulator /usr/bin/xfce4-terminal 50
 # Set xfce4-terminal as the default x-terminal-emulator
 RUN update-alternatives --set x-terminal-emulator /usr/bin/xfce4-terminal
 
+# Create and set the XDG_RUNTIME_DIR
+RUN mkdir -p /tmp/runtime
+
+# Set environment variables for the user
+ENV XDG_RUNTIME_DIR=/tmp/runtime

.devcontainer/devcontainer.json

@@ -15,7 +15,7 @@
   },
 
   // Use 'forwardPorts' to make a list of ports inside the container available locally.
-  "forwardPorts": [5901],
+  "forwardPorts": [5900],
 
   // Use 'postCreateCommand' to run commands after the container is created.
   "postCreateCommand": "sudo ./.devcontainer/setup.sh",

.devcontainer/setup.sh

@@ -1,9 +1,8 @@
 #! /bin/bash
 
-touch .Xauthority
+Xvfb :1 -screen 0 1920x1080x24 &
+export DISPLAY=:1
 
-umask 0077
-mkdir -p "$HOME/.vnc"
-chmod go-rwx "$HOME/.vnc"
-vncpasswd -f <<<"unipept" >"$HOME/.vnc/passwd"
-vncserver -geometry 1920x1080
+startxfce4 &
+
+x11vnc -display :1