diff --git a/.ci/helpers.sh b/.ci/helpers.sh
index 8cc26e6..0279d67 100644
--- a/.ci/helpers.sh
+++ b/.ci/helpers.sh
@@ -114,6 +114,11 @@ install_packages_needed_for_functional_tests() {
   apt-get install -y python3 python3-pip python3-boto3 curl pkg-config libxmlsec1-dev
 }
 
+is_build_this_distro() {
+  local distro="$1"
+  [[ "$BUILD_DISTROS_REGEX" = 'all' ]] || [[ "$distro" =~ $BUILD_DISTROS_REGEX ]]
+}
+
 function upload_to_s3() {
   local file_to_upload="$1";
   local s3_url_for_file="$2";
@@ -132,7 +137,7 @@ function prepare_s3_uploader() {
 function prepare_to_run_scripts_and_s3_uploads() {
   export DEBIAN_FRONTEND=noninteractive
   apt-get update
-  apt-get install -y ruby2.7 git wget
+  apt-get install -y ruby3.1 git wget
   apt-get install -y python3 python3-pip python3-boto3 curl pkg-config libxmlsec1-dev
   prepare_s3_uploader
 }
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 65b2f88..a839c2c 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -7,10 +7,15 @@ variables:
   GITLAB_SHARED_DIND_DIR: /builds/$CI_PROJECT_PATH/shared
   GIT_SUBMODULE_STRATEGY: normal
   GIT_FETCH_EXTRA_FLAGS: --tags --force
-  # E.g. BUILD_JOBS: build_debian_buster,build_ubuntu_focal. This will include
-  # arm builds, because build_debian_buster_arm matches build_debian_buster.
-  # "BUILD_JOBS: none" won't build any build jobs, nor www.
-  BUILD_JOBS: all
+  # For example, BUILD_DISTROS_REGEX: "jammy|focal".
+  # "BUILD_DISTROS_REGEX: none" won't build any distros, nor www.
+  # "BUILD_DISTROS_REGEX: all" would build all distros.
+  # Make sure you quote any whitespace characters you use.
+  # E.g. BUILD_DISTROS_REGEX: "jammy|\ focal".
+  BUILD_DISTROS_REGEX: all
+  # To debug upload stage, you can limit BUILD_DISTROS_REGEX to jammy and allow
+  # run_test distros to fail, by setting ALLOW_RUN_TESTS_TO_FAIL to true.
+  ALLOW_RUN_TESTS_TO_FAIL: false
   DOCKER_HOST: tcp://docker:2375
   DOCKER_TLS_CERTDIR: ""
 
@@ -29,8 +34,8 @@ stages:
 
 .prepare_build: &prepare_build
   - pwd
-  - apk add bash
   - mkdir -p "$GITLAB_SHARED_DIND_DIR" && chmod 777 "$GITLAB_SHARED_DIND_DIR"
+  - apt-get update && apt-get install -y docker.io
   - docker login --username $DOCKER_HUB_USERNAME --password $DOCKER_HUB_PASSWORD
 
 .prepare_www: &prepare_www
@@ -46,7 +51,7 @@ default:
 
 functional_test:
   stage: functional_test
-  image: debian:bookworm
+  image: debian:bookworm-slim
   tags:
     - oci-fixed-amd
   before_script:
@@ -82,7 +87,7 @@ build_www:
     - tar -zcvf ../output/www/kasm_www.tar.gz www
   only:
     variables:
-      - $BUILD_JOBS !~ /^none$/
+      - $BUILD_DISTROS_REGEX !~ /^none$/
   artifacts:
     paths:
       - output/
@@ -90,18 +95,18 @@ build_www:
 build_amd64:
   stage: build
   allow_failure: true
+  image: debian:bookworm-slim
   tags:
     - oci-fixed-amd
   before_script:
     - *prepare_build
     - *prepare_www
+    - . .ci/helpers.sh
   after_script:
     - *prepare_artfacts
   script:
-    - bash builder/build-package $DISTRO;
-  only:
-    variables:
-      - $BUILD_JOBS == 'all' || $BUILD_JOBS =~ "$DISTRO"
+    - set -e
+    - is_build_this_distro "$DISTRO" && builder/build-package $DISTRO
   artifacts:
     paths:
       - output/
@@ -112,18 +117,18 @@ build_amd64:
 build_arm64:
   stage: build
   allow_failure: true
+  image: debian:bookworm-slim
   tags:
     - oci-fixed-arm
   before_script:
     - *prepare_build
     - *prepare_www
+    - . .ci/helpers.sh
   after_script:
     - *prepare_artfacts
   script:
-    - bash builder/build-package $DISTRO;
-  only:
-    variables:
-      - $BUILD_JOBS == 'all' || $BUILD_JOBS =~ "$DISTRO"
+    - set -e
+    - is_build_this_distro "$DISTRO" && builder/build-package $DISTRO
   artifacts:
     paths:
       - output/
@@ -133,15 +138,19 @@ build_arm64:
 
 run_test_amd64:
   stage: run_test
+  image: debian:bookworm-slim
   tags:
     - oci-fixed-amd
   before_script:
     - *prepare_build
+    - . .ci/helpers.sh
   script:
-    - bash builder/test-barebones --run-test $DISTRO
-  only:
-    variables:
-      - $BUILD_JOBS == 'all' || $BUILD_JOBS =~ "$DISTRO"
+    - set -e
+    - is_build_this_distro "$DISTRO" && builder/test-barebones --run-test $DISTRO
+  rules:
+    - if: $ALLOW_RUN_TESTS_TO_FAIL == "false"
+    - if: $ALLOW_RUN_TESTS_TO_FAIL == "true"
+      allow_failure: true
   dependencies:
     - build_amd64
   artifacts:
@@ -154,15 +163,19 @@ run_test_amd64:
 
 run_test_arm64:
   stage: run_test
+  image: debian:bookworm-slim
   tags:
     - oci-fixed-arm
   before_script:
     - *prepare_build
+    - . .ci/helpers.sh
   script:
-    - bash builder/test-barebones --run-test $DISTRO
-  only:
-    variables:
-      - $BUILD_JOBS == 'all' || $BUILD_JOBS =~ "$DISTRO"
+    - set -e
+    - is_build_this_distro "$DISTRO" && builder/test-barebones --run-test $DISTRO
+  rules:
+    - if: $ALLOW_RUN_TESTS_TO_FAIL == "false"
+    - if: $ALLOW_RUN_TESTS_TO_FAIL == "true"
+      allow_failure: true
   dependencies:
     - build_arm64
   artifacts:
@@ -175,6 +188,7 @@ run_test_arm64:
 
 spec_test:
   stage: test
+  image: debian:bookworm-slim
   tags:
     - kasmvnc-x86
   before_script:
@@ -185,12 +199,12 @@ spec_test:
         - SelfBench.xml
         - Benchmark.xml
   script:
-    - bash builder/test-vncserver
+    - builder/test-vncserver
 
 
 upload:
   stage: upload
-  image: ubuntu:focal
+  image: debian:bookworm-slim
   tags:
     - oci-fixed-amd
   artifacts:
@@ -229,7 +243,7 @@ upload_build_preview:
   stage: upload
   needs: ["upload"]
   dependencies: ["upload"]
-  image: ubuntu:focal
+  image: debian:bookworm-slim
   tags:
     - oci-fixed-amd
   before_script:
diff --git a/BUILDING.txt b/BUILDING.md
similarity index 67%
rename from BUILDING.txt
rename to BUILDING.md
index 4cd1a8e..668e488 100644
--- a/BUILDING.txt
+++ b/BUILDING.md
@@ -1,78 +1,6 @@
-*******************************************************************************
-**     Building KasmVNC
-*******************************************************************************
+# Building KasmVNC
 
-
-================================
-Build Requirements (All Systems)
-================================
-
--- CMake (http://www.cmake.org) v2.8 or later
-
--- zlib
-
--- If building TLS support:
-   * GnuTLS 3.x
-   * See "Building TLS Support" below.
-
--- If building native language support (NLS):
-   * Gnu gettext 0.14.4 or later
-   * See "Building Native Language Support" below.
-
--- libjpeg-turbo
-   * "Normal" libjpegv6 is also supported, although it is not
-     recommended as it is much slower.
-
--- libwebp
-
-
-=========================
-Build Requirements (Unix)
-=========================
-
--- Non-Mac platforms:
-   * X11 development kit
-
--- If building Xvnc/libvnc.so:
-   * Xorg server source code, 1.7 or never
-   * All build requirements Xorg imposes (see its documentation)
-
-============================
-Build Requirements (Windows)
-============================
-
--- MinGW or MinGW-w64
-
--- Inno Setup (needed to build the KasmVNC installer)
-   Inno Setup can be downloaded from http://www.jrsoftware.org/isinfo.php.
-   You also need the Inno Setup Preprocessor, which is available in the
-   Inno Setup QuickStart Pack.
-
-   Add the directory containing iscc.exe (for instance,
-   C:\Program Files\Inno Setup 5) to the system or user PATH environment
-   variable prior to building KasmVNC.
-
-
-==================
-Out-of-Tree Builds
-==================
-
-Binary objects, libraries, and executables are generated in the same directory
-from which cmake was executed (the "binary directory"), and this directory need
-not necessarily be the same as the KasmVNC source directory.  You can create
-multiple independent binary directories, in which different versions of
-KasmVNC can be built from the same source tree using different compilers or
-settings.  In the sections below, {build_directory} refers to the binary
-directory, whereas {source_directory} refers to the KasmVNC source directory.
-For in-tree builds, these directories are the same.
-
-
-=================
-Building KasmVNC
-=================
-
-Building the KasmVNC Server using Docker
-----------------------------------------
+## Building the KasmVNC Server using Docker
 
 ```bash
 git submodule init
@@ -81,6 +9,9 @@ sudo docker build -t kasmvnc:dev -f builder/dockerfile.ubuntu_jammy.dev .
 sudo docker run -it --rm -v ./:/src -p 6901:6901 -p 8443:8443 --name kasmvnc_dev kasmvnc:dev
 ```
 
+**The above assumes you are UID 1000 on the host as the container UID is 1000.**
+Ensure you switch to the user associated to UID 1000 on the host.
+
 Now from inside the container.
 
 ```bash
@@ -99,14 +30,13 @@ builder/build.sh
 Now run Xvnc and Xfce4 from inside the container
 
 ```bash
-/src/xorg.build/bin/Xvnc -interface 0.0.0.0 -PublicIP 127.0.0.1 -disableBasicAuth -RectThreads 0 -Log *:stdout:100 -httpd /src/kasmweb/dist -sslOnly 0 -SecurityTypes None -websocketPort 6901  :1 &
+/src/xorg.build/bin/Xvnc -interface 0.0.0.0 -PublicIP 127.0.0.1 -disableBasicAuth -RectThreads 0 -Log *:stdout:100 -httpd /src/kasmweb/dist -sslOnly 0 -SecurityTypes None -websocketPort 6901 -FreeKeyMappings :1 &
 /usr/bin/xfce4-session --display :1
 ```
 
 Now open a browser and navigate to your dev VM on port 6901.
 
-Running noVNC from source
--------------------------
+## Running noVNC from source
 If you need to debug or make changes to the UI code, use the following procedures to use npm to serve the web code. The code will automatically rebuild when changes are made and the code will not be packaged.
 These steps assume you are inside the kasmvnc:dev container started in the above steps.
 
@@ -114,7 +44,7 @@ Now from inside the container. **This assumes KasmVNC is already built, follow s
 
 ```bash
 # Run KasmVNC
-/src/xorg.build/bin/Xvnc -interface 0.0.0.0 -PublicIP 127.0.0.1 -disableBasicAuth -RectThreads 0 -Log *:stdout:100 -httpd /src/kasmweb/dist -sslOnly 0 -SecurityTypes None -websocketPort 6901  :1 &
+/src/xorg.build/bin/Xvnc -interface 0.0.0.0 -PublicIP 127.0.0.1 -disableBasicAuth -RectThreads 0 -Log *:stdout:100 -httpd /src/kasmweb/dist -sslOnly 0 -SecurityTypes None -websocketPort 6901 -FreeKeyMappings :1 &
 /usr/bin/xfce4-session --display :1 &
 
 sudo nginx
@@ -133,8 +63,60 @@ Since `npm run serve` needs to run in the foreground, you may need to exec into
 sudo docker exec -it kasmvnc_dev /bin/bash
 ```
 
-Building the KasmVNC Server on Modern Unix/Linux Systems
----------------------------------------------------------
+## Building in CI
+
+### Achieve a faster feedback loop in CI
+
+To achieve a faster feedback loop in CI, you can limit built distros to a few
+distros you're interested in.
+
+#### Best way to debug CI in a fast feedback loop
+
+Specify `BUILD_DISTROS_REGEX: "jammy"`, and build only Ubuntu Jammy. That's
+only 2 distro package build jobs, one for amd64 and one for arm64.
+
+Specify `ALLOW_RUN_TESTS_TO_FAIL: true` to ignore `run_test` job failures and
+debug the upload stage.
+
+#### Build only a few distros
+
+To build only distros you want, specify a regex in `$BUILD_DISTROS_REGEX`
+variable.  For example, build Ubuntu Jammy and Focal with `BUILD_DISTROS_REGEX:
+"jammy|focal"`. Or simply a single distro Ubuntu Jammy with
+`BUILD_DISTROS_REGEX: "jammy"`.<br>
+To build all distros, specify `BUILD_DISTROS_REGEX: all`.<br>
+To build no distros, and no www, specify `BUILD_DISTROS_REGEX: none`.
+
+##### Required distros to build
+
+Functional tests and spec tests use Ubuntu Jammy. If Jammy is not built, those
+stages fail. If you want to debug pipeline stages after `functional_test`,
+building Ubuntu Jammy is required.
+
+Specify `BUILD_DISTROS_REGEX: "jammy|<distro_you're_interested_in>"`.
+
+##### Heed, when writing regex
+
+Regex placed in `$BUILD_DISTROS_REGEX` are [Bash
+regex](https://tldp.org/LDP/Bash-Beginners-Guide/html/sect_04_01.html) and are
+processed by Bash.
+
+Any whitespace in `$BUILD_DISTROS_REGEX` must be escaped. For example,
+`BUILD_DISTROS_REGEX: "\ jammy"`.
+
+#### Debug upload stage, while building only a few distros
+
+`run_test` jobs fail the pipeline, whenever packages for a distro weren't
+built. When building only a few distros, packages for the rest of distros aren't
+built. Not finding the package to test, a `run_test` job fails, pipeline fails,
+and the upload stage doesn't get executed.
+
+To still execute and debug upload stage in a faster feedback loop (building only
+a few distros), specify `ALLOW_RUN_TESTS_TO_FAIL: true`.  Gitlab CI's
+`allow_failure: true` is used to allow the pipeline to ignore failed `run_test`
+jobs and continue to the upload stage.
+
+## Building the KasmVNC Server on Modern Unix/Linux Systems
 
 Building the KasmVNC Server (Xvnc) is a bit trickier.  On newer systems
 containing Xorg 7.4 or later (such as Fedora), Xvnc is typically built to use
@@ -142,48 +124,49 @@ the X11 shared libraries provided with the system.  The procedure for this is
 system-specific, since it requires specifying such things as font directories,
 but the general outline is as follows.
 
-  > cd {build_directory}
+```bash
+  cd {build_directory}
 
-    If performing an out-of-tree build:
-  > mkdir unix
-  > cp -R {source_directory}/unix/xserver unix/
+  # If performing an out-of-tree build:
+  mkdir unix
+  cp -R {source_directory}/unix/xserver unix/
 
-  > cp -R {xorg_source}/* unix/xserver/
-    (NOTE: {xorg_source} is the directory containing the Xorg source for the
-    machine on which you are building KasmVNC.  The most recent versions of
-    Red Hat/Fedora, for instance, provide an RPM called
-    "xorg-x11-server-source", which installs the Xorg source under
-    /usr/share/xorg-x11-server-source.)
+  cp -R {xorg_source}/* unix/xserver/
+  # (NOTE: {xorg_source} is the directory containing the Xorg source for the
+  # machine on which you are building KasmVNC.  The most recent versions of
+  # Red Hat/Fedora, for instance, provide an RPM called
+  # "xorg-x11-server-source", which installs the Xorg source under
+  # /usr/share/xorg-x11-server-source.)
 
-  > cd unix/xserver/
-  > patch -p1 < {source_directory}/unix/xserver{version}.patch
-    (where {version} matches the X server version you are building, such as
-    "17" for version 1.7.x.)
-  > autoreconf -fiv
+  cd unix/xserver/
+  patch -p1 < {source_directory}/unix/xserver{version}.patch
+  (where {version} matches the X server version you are building, such as
+  "17" for version 1.7.x.)
+  autoreconf -fiv
 
-  > ./configure --with-pic --without-dtrace --disable-static --disable-dri \
-      --disable-xinerama --disable-xvfb --disable-xnest --disable-xorg \
-      --disable-dmx --disable-xwin --disable-xephyr --disable-kdrive \
-      --disable-config-dbus --disable-config-hal --disable-config-udev \
-      --disable-dri2 --enable-install-libxf86config --enable-glx \
-      --with-default-font-path="catalogue:/etc/X11/fontpath.d,built-ins" \
-      --with-fontdir=/usr/share/X11/fonts \
-      --with-xkb-path=/usr/share/X11/xkb \
-      --with-xkb-output=/var/lib/xkb \
-      --with-xkb-bin-directory=/usr/bin \
-      --with-serverconfig-path=/usr/lib[64]/xorg \
-      --with-dri-driver-path=/usr/lib[64]/dri \
-      {additional configure options}
-    (NOTE: This is merely an example that works with Red Hat Enterprise
-    and recent Fedora releases.  You should customize it for your particular
-    system.  In particular, it will be necessary to customize the font, XKB,
-    and DRI directories.)
+  ./configure --with-pic --without-dtrace --disable-static --disable-dri \
+    --disable-xinerama --disable-xvfb --disable-xnest --disable-xorg \
+    --disable-dmx --disable-xwin --disable-xephyr --disable-kdrive \
+    --disable-config-dbus --disable-config-hal --disable-config-udev \
+    --disable-dri2 --enable-install-libxf86config --enable-glx \
+    --with-default-font-path="catalogue:/etc/X11/fontpath.d,built-ins" \
+    --with-fontdir=/usr/share/X11/fonts \
+    --with-xkb-path=/usr/share/X11/xkb \
+    --with-xkb-output=/var/lib/xkb \
+    --with-xkb-bin-directory=/usr/bin \
+    --with-serverconfig-path=/usr/lib[64]/xorg \
+    --with-dri-driver-path=/usr/lib[64]/dri \
+    {additional configure options}
+    # (NOTE: This is merely an example that works with Red Hat Enterprise
+    # and recent Fedora releases.  You should customize it for your particular
+    # system.  In particular, it will be necessary to customize the font, XKB,
+    # and DRI directories.)
 
-  > make KASMVNC_SRCDIR={source_directory}
+  make KASMVNC_SRCDIR={source_directory}
+```
 
 
-Building the KasmVNC Server on Legacy Unix/Linux Systems
----------------------------------------------------------
+## Building the KasmVNC Server on Legacy Unix/Linux Systems
 
 Those using systems with older versions of Xorg must build a "legacy-friendly"
 version of the KasmVNC Server.  This is accomplished by downloading and
@@ -195,9 +178,11 @@ source distribution (located under contrib/xorg/) automates this process.
 The following procedure will build a
 "legacy-friendly" version of the KasmVNC Server:
 
+```bash
   cd {build_directory}
   sh {source_directory}/contrib/xorg/build-xorg init
   sh {source_directory}/contrib/xorg/build-xorg build [additional CMake flags]
+```
 
 build-xorg generates a version of Xvnc that has no external dependencies on the
 X11 shared libraries or any other distribution-specific shared libraries.  This
@@ -211,30 +196,32 @@ once the X11 modules and other dependencies have been built for the first time.
 This is convenient for testing changes that just apply to the KasmVNC source
 code.  To accomplish this, run:
 
+```sh
   sh {source_directory}/contrib/xorg/build-xorg rebuild [additional make flags]
+```
 
 For instance,
 
+```sh
   sh {source_directory}/contrib/xorg/build-xorg rebuild clean
+```
 
 will clean the Xvnc build without destroying any of the
 build configuration or module dependencies.
 
 
-Debug Build
------------
+## Debug Build
 
-Add "-DCMAKE_BUILD_TYPE=Debug" to the CMake command line.
+Add `-DCMAKE_BUILD_TYPE=Debug` to the CMake command line.
 
 
-Portable (semi-static) Build
-----------------------------
+## Portable (semi-static) Build
 
 KasmVNC can under favourble circumstances be built in a way that allows
 the resulting binaries to run on any system without having to also install
 all the dynamic libraries it depends on. Enable this mode by adding:
 
-  -DBUILD_STATIC=1
+  `-DBUILD_STATIC=1`
 
 to the CMake command line.
 
@@ -242,30 +229,53 @@ Note that the method used to achieve this is very fragile and it may be
 necessary to tweak cmake/StaticBuild.cmake to make things work on your
 specific system.
 
+# Build Requirements (Windows)
 
-======================================
-Building TLS Support
-======================================
+-- MinGW or MinGW-w64
+
+-- Inno Setup (needed to build the KasmVNC installer)
+   Inno Setup can be downloaded from http://www.jrsoftware.org/isinfo.php.
+   You also need the Inno Setup Preprocessor, which is available in the
+   Inno Setup QuickStart Pack.
+
+   Add the directory containing iscc.exe (for instance,
+   C:\Program Files\Inno Setup 5) to the system or user PATH environment
+   variable prior to building KasmVNC.
+
+
+# Out-of-Tree Builds
+
+Binary objects, libraries, and executables are generated in the same directory
+from which cmake was executed (the "binary directory"), and this directory need
+not necessarily be the same as the KasmVNC source directory.  You can create
+multiple independent binary directories, in which different versions of
+KasmVNC can be built from the same source tree using different compilers or
+settings.  In the sections below, {build_directory} refers to the binary
+directory, whereas {source_directory} refers to the KasmVNC source directory.
+For in-tree builds, these directories are the same.
+
+
+# Building TLS Support
 
 TLS requires GnuTLS, which is supplied with most Linux distributions and
 with MinGW for Windows and can be built from source on OS X and other
 Unix variants. However, GnuTLS versions > 2.12.x && < 3.3.x should be
 avoided because of potential incompatibilities during initial handshaking.
 
-You can override the GNUTLS_LIBRARY and GNUTLS_INCLUDE_DIR CMake variables
+You can override the `GNUTLS_LIBRARY` and `GNUTLS_INCLUDE_DIR` CMake variables
 to specify the locations of libgnutls and any dependencies.  For instance,
 adding
 
+```bash
   -DGNUTLS_INCLUDE_DIR=/usr/local/include \
   -DGNUTLS_LIBRARY=/usr/local/lib/libgnutls.a
+```
 
 to the CMake command line would link KasmVNC against a static version of
 libgnutls located under /usr/local.
 
 
-======================================
-Building Native Language Support (NLS)
-======================================
+# Building Native Language Support (NLS)
 
 NLS requires gettext, which is supplied with most Linux distributions and
 with MinGW for Windows and which can easily be built from source on OS X and
@@ -275,60 +285,57 @@ You can override the ICONV_LIBRARIES and LIBINTL_LIBRARY CMake variables to
 specify the locations of libiconv and libintl, respectively.  For instance,
 adding
 
-  -DLIBINTL_LIBRARY=/opt/gettext/lib/libintl.a
+  `-DLIBINTL_LIBRARY=/opt/gettext/lib/libintl.a`
 
 to the CMake command line would link KasmVNC against a static version of
 libintl located under /opt/gettext.  Adding
 
+```bash
   -DICONV_INCLUDE_DIR=/mingw/include \
     -DICONV_LIBRARIES=/mingw/lib/libiconv.a \
     -DGETTEXT_INCLUDE_DIR=/mingw/include \
     -DLIBINTL_LIBRARY=/mingw/lib/libintl.a
+```
 
 to the CMake command line would link KasmVNC against the static versions of
 libiconv and libintl included in the MinGW Developer Toolkit.
 
 
-===================
-Installing KasmVNC
-===================
+# Installing KasmVNC
 
 You can use the build system to install KasmVNC into a directory of your
 choosing.  To do this, add:
 
-  -DCMAKE_INSTALL_PREFIX={install_directory}
+  `-DCMAKE_INSTALL_PREFIX={install_directory}`
 
 to the CMake command line.  Then, you can run 'make install' to build and
 install it.
 
-If you don't specify CMAKE_INSTALL_PREFIX, then the default is
-c:\Program Files\KasmVNC on Windows and /usr/local on Unix.
+If you don't specify `CMAKE_INSTALL_PREFIX`, then the default is
+`c:\Program Files\KasmVNC` on Windows and `/usr/local` on Unix.
 
 
-=========================
-Creating Release Packages
-=========================
+# Creating Release Packages
 
 The following commands can be used to create various types of release packages:
 
 
-Unix
-----
+## Unix
 
-make tarball
+`make tarball`
 
   Create a binary tarball containing the utils
 
-make servertarball
+`make servertarball`
 
   Create a binary tarball containing both the KasmVNC Server and utils
 
-make dmg
+`make dmg`
 
   Create Macintosh disk image file that contains an application bundle of the
   utils
 
-make udmg
+`make udmg`
 
   On 64-bit OS X systems, this creates a version of the Macintosh package and
   disk image which contains universal i386/x86-64 binaries.  You should first
@@ -341,67 +348,69 @@ make udmg
   using the instructions in the "Build Recipes" section.
 
 
-Windows
--------
+## Windows
 
-make installer
+`make installer`
 
   Create a Windows installer using Inno Setup.  The installer package
   (KasmVNC[64].exe) will be located under {build_directory}.
 
 
-=============
-Build Recipes
-=============
+# Build Recipes
 
 
-32-bit Build on 64-bit Linux/Unix (including OS X)
---------------------------------------------------
+## 32-bit Build on 64-bit Linux/Unix (including OS X)
 
 Set the following environment variables before building KasmVNC.
 
+```bash
   CFLAGS='-O3 -m32'
   CXXFLAGS='-O3 -m32'
   LDFLAGS=-m32
+```
 
 If you are building the KasmVNC Server on a modern Unix/Linux system, then
 you will also need to pass the appropriate --host argument when configuring the
 X server source (for instance, --host=i686-pc-linux-gnu).
 
 
-64-bit Backward-Compatible Build on 64-bit OS X
------------------------------------------------
+## 64-bit Backward-Compatible Build on 64-bit OS X
 
 Add
 
+```bash
   -DCMAKE_OSX_SYSROOT=/Developer/SDKs/MacOSX10.5.sdk \
     -DCMAKE_OSX_DEPLOYMENT_TARGET=10.5
+```
 
 to the CMake command line.  The OS X 10.5 SDK must be installed.
 
 
-32-bit Backward-Compatible Build on 64-bit OS X
------------------------------------------------
+## 32-bit Backward-Compatible Build on 64-bit OS X
 
 Set the following environment variables:
 
+```bash
   CC=gcc-4.0
   CXX=g++-4.0
   CFLAGS='-O3 -m32'
   CXXFLAGS='-O3 -m32'
   LDFLAGS=-m32
+```
 
 and add
 
+```bash
   -DCMAKE_OSX_SYSROOT=/Developer/SDKs/MacOSX10.4u.sdk \
     -DCMAKE_OSX_DEPLOYMENT_TARGET=10.4
+```
 
 to the CMake command line.  The OS X 10.4 SDK must be installed.
 
 
-64-bit MinGW Build on Cygwin
-----------------------------
+## 64-bit MinGW Build on Cygwin
 
+```bash
   cd {build_directory}
   CC=/usr/bin/x86_64-w64-mingw32-gcc CXX=/usr/bin/x86_64-w64-mingw32-g++ \
     RC=/usr/bin/x86_64-w64-mingw32-windres \
@@ -409,15 +418,16 @@ to the CMake command line.  The OS X 10.4 SDK must be installed.
     -DCMAKE_AR=/usr/bin/x86_64-w64-mingw32-ar \
     -DCMAKE_RANLIB=/usr/bin/x86_64-w64-mingw32-ranlib {source_directory}
   make
+```
 
 This produces a 64-bit build of KasmVNC that does not depend on cygwin1.dll or
 other Cygwin DLL's.  The mingw64-x86_64-gcc-core and mingw64-x86_64-gcc-g++
 packages (and their dependencies) must be installed.
 
 
-32-bit MinGW Build on Cygwin
-----------------------------
+## 32-bit MinGW Build on Cygwin
 
+```bash
   cd {build_directory}
   CC=/usr/bin/i686-w64-mingw32-gcc CXX=/usr/bin/i686-w64-mingw32-g++ \
     RC=/usr/bin/i686-w64-mingw32-windres \
@@ -425,18 +435,19 @@ packages (and their dependencies) must be installed.
     -DDCMAKE_AR=/usr/bin/i686-w64-mingw32-ar \
     -DCMAKE_RANLIB=/usr/bin/i686-w64-mingw32-ranlib {source_directory}
   make
+```
 
 This produces a 32-bit build of KasmVNC that does not depend on cygwin1.dll or
 other Cygwin DLL's.  The mingw64-i686-gcc-core and mingw64-i686-gcc-g++
 packages (and their dependencies) must be installed.
 
 
-MinGW-w64 Build on Windows
---------------------------
+## MinGW-w64 Build on Windows
 
 This produces a 64-bit build of KasmVNC using the "native" MinGW-w64 toolchain
 (which is faster than the Cygwin version):
 
+```bash
   cd {build_directory}
   CC={mingw-w64_binary_path}/x86_64-w64-mingw32-gcc \
     CXX={mingw-w64_binary_path}/x86_64-w64-mingw32-g++ \
@@ -446,11 +457,12 @@ This produces a 64-bit build of KasmVNC using the "native" MinGW-w64 toolchain
     -DCMAKE_RANLIB={mingw-w64_binary_path}/x86_64-w64-mingw32-ranlib \
     {source_directory}
   make
+```
 
 
-MinGW Build on Linux
---------------------
+## MinGW Build on Linux
 
+```bash
   cd {build_directory}
   CC={mingw_binary_path}/i386-mingw32-gcc \
     CXX={mingw_binary_path}/i386-mingw32-g++ \
@@ -460,15 +472,13 @@ MinGW Build on Linux
     -DCMAKE_RANLIB={mingw_binary_path}/i386-mingw32-ranlib \
     {source_directory}
   make
+```
 
 
-===============================
-Distribution-Specific Packaging
-===============================
+# Distribution-Specific Packaging
 
 
-RPM Packages for RHEL
-------------------------------
+## RPM Packages for RHEL
 
 The RPM spec files and patches used to create the nightly builds
 and releases can be found in the "contrib/rpm/el{5,6}" directories
@@ -477,6 +487,7 @@ must be fetched manually and placed into the 'SOURCES' directory
 under the rpmbuild root.  Additionally, the following macros need
 to be defined:
 
+```
   EL6:
     %debug_package %{nil}
 
@@ -485,10 +496,11 @@ to be defined:
     %_smp_mflags  -j3
     %debug_package %{nil}
     %__arch_install_post   /usr/lib/rpm/check-rpaths   /usr/lib/rpm/check-buildroot
+```
 
 
-Debian packages for Ubuntu 12.04LTS
------------------------------------
+## Debian packages for Ubuntu 12.04LTS
+
 The debian folder used to create the nightly builds and releases
 can be found in the "contrib/deb/ubuntu-precise" directory of the
 KasmVNC subversion trunk.
diff --git a/Pipfile b/Pipfile
index aa90173..42edbba 100644
--- a/Pipfile
+++ b/Pipfile
@@ -12,4 +12,4 @@ pexpect = "*"
 [dev-packages]
 
 [requires]
-python_version = "3.8"
+python_version = "3.10"
diff --git a/Pipfile.lock b/Pipfile.lock
index 1006c73..68f1a32 100644
--- a/Pipfile.lock
+++ b/Pipfile.lock
@@ -1,11 +1,11 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "6745d5e5d90e44a18d73a0e23bc3d3e68acb950af0b87df50b45272d25b9e615"
+            "sha256": "f6a1fc809d6e02cd4f1ed8e45d4fc135a7c757cabe8eeb887a29e3664b796221"
         },
         "pipfile-spec": 6,
         "requires": {
-            "python_version": "3.8"
+            "python_version": "3.10"
         },
         "sources": [
             {
@@ -30,61 +30,72 @@
         },
         "coverage": {
             "hashes": [
-                "sha256:004d1880bed2d97151facef49f08e255a20ceb6f9432df75f4eef018fdd5a78c",
-                "sha256:01d84219b5cdbfc8122223b39a954820929497a1cb1422824bb86b07b74594b6",
-                "sha256:040af6c32813fa3eae5305d53f18875bedd079960822ef8ec067a66dd8afcd45",
-                "sha256:06191eb60f8d8a5bc046f3799f8a07a2d7aefb9504b0209aff0b47298333302a",
-                "sha256:13034c4409db851670bc9acd836243aeee299949bd5673e11844befcb0149f03",
-                "sha256:13c4ee887eca0f4c5a247b75398d4114c37882658300e153113dafb1d76de529",
-                "sha256:184a47bbe0aa6400ed2d41d8e9ed868b8205046518c52464fde713ea06e3a74a",
-                "sha256:18ba8bbede96a2c3dde7b868de9dcbd55670690af0988713f0603f037848418a",
-                "sha256:1aa846f56c3d49205c952d8318e76ccc2ae23303351d9270ab220004c580cfe2",
-                "sha256:217658ec7187497e3f3ebd901afdca1af062b42cfe3e0dafea4cced3983739f6",
-                "sha256:24d4a7de75446be83244eabbff746d66b9240ae020ced65d060815fac3423759",
-                "sha256:2910f4d36a6a9b4214bb7038d537f015346f413a975d57ca6b43bf23d6563b53",
-                "sha256:2949cad1c5208b8298d5686d5a85b66aae46d73eec2c3e08c817dd3513e5848a",
-                "sha256:2a3859cb82dcbda1cfd3e6f71c27081d18aa251d20a17d87d26d4cd216fb0af4",
-                "sha256:2cafbbb3af0733db200c9b5f798d18953b1a304d3f86a938367de1567f4b5bff",
-                "sha256:2e0d881ad471768bf6e6c2bf905d183543f10098e3b3640fc029509530091502",
-                "sha256:30c77c1dc9f253283e34c27935fded5015f7d1abe83bc7821680ac444eaf7793",
-                "sha256:3487286bc29a5aa4b93a072e9592f22254291ce96a9fbc5251f566b6b7343cdb",
-                "sha256:372da284cfd642d8e08ef606917846fa2ee350f64994bebfbd3afb0040436905",
-                "sha256:41179b8a845742d1eb60449bdb2992196e211341818565abded11cfa90efb821",
-                "sha256:44d654437b8ddd9eee7d1eaee28b7219bec228520ff809af170488fd2fed3e2b",
-                "sha256:4a7697d8cb0f27399b0e393c0b90f0f1e40c82023ea4d45d22bce7032a5d7b81",
-                "sha256:51cb9476a3987c8967ebab3f0fe144819781fca264f57f89760037a2ea191cb0",
-                "sha256:52596d3d0e8bdf3af43db3e9ba8dcdaac724ba7b5ca3f6358529d56f7a166f8b",
-                "sha256:53194af30d5bad77fcba80e23a1441c71abfb3e01192034f8246e0d8f99528f3",
-                "sha256:5fec2d43a2cc6965edc0bb9e83e1e4b557f76f843a77a2496cbe719583ce8184",
-                "sha256:6c90e11318f0d3c436a42409f2749ee1a115cd8b067d7f14c148f1ce5574d701",
-                "sha256:74d881fc777ebb11c63736622b60cb9e4aee5cace591ce274fb69e582a12a61a",
-                "sha256:7501140f755b725495941b43347ba8a2777407fc7f250d4f5a7d2a1050ba8e82",
-                "sha256:796c9c3c79747146ebd278dbe1e5c5c05dd6b10cc3bcb8389dfdf844f3ead638",
-                "sha256:869a64f53488f40fa5b5b9dcb9e9b2962a66a87dab37790f3fcfb5144b996ef5",
-                "sha256:8963a499849a1fc54b35b1c9f162f4108017b2e6db2c46c1bed93a72262ed083",
-                "sha256:8d0a0725ad7c1a0bcd8d1b437e191107d457e2ec1084b9f190630a4fb1af78e6",
-                "sha256:900fbf7759501bc7807fd6638c947d7a831fc9fdf742dc10f02956ff7220fa90",
-                "sha256:92b017ce34b68a7d67bd6d117e6d443a9bf63a2ecf8567bb3d8c6c7bc5014465",
-                "sha256:970284a88b99673ccb2e4e334cfb38a10aab7cd44f7457564d11898a74b62d0a",
-                "sha256:972c85d205b51e30e59525694670de6a8a89691186012535f9d7dbaa230e42c3",
-                "sha256:9a1ef3b66e38ef8618ce5fdc7bea3d9f45f3624e2a66295eea5e57966c85909e",
-                "sha256:af0e781009aaf59e25c5a678122391cb0f345ac0ec272c7961dc5455e1c40066",
-                "sha256:b6d534e4b2ab35c9f93f46229363e17f63c53ad01330df9f2d6bd1187e5eaacf",
-                "sha256:b7895207b4c843c76a25ab8c1e866261bcfe27bfaa20c192de5190121770672b",
-                "sha256:c0891a6a97b09c1f3e073a890514d5012eb256845c451bd48f7968ef939bf4ae",
-                "sha256:c2723d347ab06e7ddad1a58b2a821218239249a9e4365eaff6649d31180c1669",
-                "sha256:d1f8bf7b90ba55699b3a5e44930e93ff0189aa27186e96071fac7dd0d06a1873",
-                "sha256:d1f9ce122f83b2305592c11d64f181b87153fc2c2bbd3bb4a3dde8303cfb1a6b",
-                "sha256:d314ed732c25d29775e84a960c3c60808b682c08d86602ec2c3008e1202e3bb6",
-                "sha256:d636598c8305e1f90b439dbf4f66437de4a5e3c31fdf47ad29542478c8508bbb",
-                "sha256:deee1077aae10d8fa88cb02c845cfba9b62c55e1183f52f6ae6a2df6a2187160",
-                "sha256:ebe78fe9a0e874362175b02371bdfbee64d8edc42a044253ddf4ee7d3c15212c",
-                "sha256:f030f8873312a16414c0d8e1a1ddff2d3235655a2174e3648b4fa66b3f2f1079",
-                "sha256:f0b278ce10936db1a37e6954e15a3730bea96a0997c26d7fee88e6c396c2086d",
-                "sha256:f11642dddbb0253cc8853254301b51390ba0081750a8ac03f20ea8103f0c56b6"
+                "sha256:042e7841a26498fff7a37d6fda770d17519982f5b7d8bf5278d140b67b61095f",
+                "sha256:04bfec25a8ef1c5f41f5e7e5c842f6b615599ca8ba8391ec33a9290d9d2db3a3",
+                "sha256:0915742f4c82208ebf47a2b154a5334155ed9ef9fe6190674b8a46c2fb89cb05",
+                "sha256:18c5ae6d061ad5b3e7eef4363fb27a0576012a7447af48be6c75b88494c6cf25",
+                "sha256:2931f66991175369859b5fd58529cd4b73582461877ecfd859b6549869287ffe",
+                "sha256:2e4b6b87bb0c846a9315e3ab4be2d52fac905100565f4b92f02c445c8799e257",
+                "sha256:3043ba1c88b2139126fc72cb48574b90e2e0546d4c78b5299317f61b7f718b78",
+                "sha256:379fe315e206b14e21db5240f89dc0774bdd3e25c3c58c2c733c99eca96f1ada",
+                "sha256:42421e04069fb2cbcbca5a696c4050b84a43b05392679d4068acbe65449b5c64",
+                "sha256:4dfd9a93db9e78666d178d4f08a5408aa3f2474ad4d0e0378ed5f2ef71640cb6",
+                "sha256:52a523153c568d2c0ef8826f6cc23031dc86cffb8c6aeab92c4ff776e7951b28",
+                "sha256:554fec1199d93ab30adaa751db68acec2b41c5602ac944bb19187cb9a41a8067",
+                "sha256:581a40c7b94921fffd6457ffe532259813fc68eb2bdda60fa8cc343414ce3733",
+                "sha256:5a26c0c795c3e0b63ec7da6efded5f0bc856d7c0b24b2ac84b4d1d7bc578d676",
+                "sha256:5a570cd9bd20b85d1a0d7b009aaf6c110b52b5755c17be6962f8ccd65d1dbd23",
+                "sha256:5aaeb00761f985007b38cf463b1d160a14a22c34eb3f6a39d9ad6fc27cb73008",
+                "sha256:5ac46d0c2dd5820ce93943a501ac5f6548ea81594777ca585bf002aa8854cacd",
+                "sha256:5c8a5c139aae4c35cbd7cadca1df02ea8cf28a911534fc1b0456acb0b14234f3",
+                "sha256:6b8af63b9afa1031c0ef05b217faa598f3069148eeee6bb24b79da9012423b82",
+                "sha256:769773614e676f9d8e8a0980dd7740f09a6ea386d0f383db6821df07d0f08545",
+                "sha256:771eb7587a0563ca5bb6f622b9ed7f9d07bd08900f7589b4febff05f469bea00",
+                "sha256:77af0f6447a582fdc7de5e06fa3757a3ef87769fbb0fdbdeba78c23049140a47",
+                "sha256:7a3d62b3b03b4b6fd41a085f3574874cf946cb4604d2b4d3e8dca8cd570ca501",
+                "sha256:821f7bcbaa84318287115d54becb1915eece6918136c6f91045bb84e2f88739d",
+                "sha256:89b1f4af0d4afe495cd4787a68e00f30f1d15939f550e869de90a86efa7e0814",
+                "sha256:8a1d96e780bdb2d0cbb297325711701f7c0b6f89199a57f2049e90064c29f6bd",
+                "sha256:8a40fcf208e021eb14b0fac6bdb045c0e0cab53105f93ba0d03fd934c956143a",
+                "sha256:8f99eb72bf27cbb167b636eb1726f590c00e1ad375002230607a844d9e9a2318",
+                "sha256:90e7fbc6216ecaffa5a880cdc9c77b7418c1dcb166166b78dbc630d07f278cc3",
+                "sha256:94ec0be97723ae72d63d3aa41961a0b9a6f5a53ff599813c324548d18e3b9e8c",
+                "sha256:95aa6ae391a22bbbce1b77ddac846c98c5473de0372ba5c463480043a07bff42",
+                "sha256:96121edfa4c2dfdda409877ea8608dd01de816a4dc4a0523356067b305e4e17a",
+                "sha256:a1f406a8e0995d654b2ad87c62caf6befa767885301f3b8f6f73e6f3c31ec3a6",
+                "sha256:a321c61477ff8ee705b8a5fed370b5710c56b3a52d17b983d9215861e37b642a",
+                "sha256:a5761c70c017c1b0d21b0815a920ffb94a670c8d5d409d9b38857874c21f70d7",
+                "sha256:a9abbccd778d98e9c7e85038e35e91e67f5b520776781d9a1e2ee9d400869487",
+                "sha256:ad80e6b4a0c3cb6f10f29ae4c60e991f424e6b14219d46f1e7d442b938ee68a4",
+                "sha256:b44674870709017e4b4036e3d0d6c17f06a0e6d4436422e0ad29b882c40697d2",
+                "sha256:b571bf5341ba8c6bc02e0baeaf3b061ab993bf372d982ae509807e7f112554e9",
+                "sha256:b8194fb8e50d556d5849753de991d390c5a1edeeba50f68e3a9253fbd8bf8ccd",
+                "sha256:b87eb6fc9e1bb8f98892a2458781348fa37e6925f35bb6ceb9d4afd54ba36c73",
+                "sha256:bbb5cc845a0292e0c520656d19d7ce40e18d0e19b22cb3e0409135a575bf79fc",
+                "sha256:be945402e03de47ba1872cd5236395e0f4ad635526185a930735f66710e1bd3f",
+                "sha256:bf13d564d310c156d1c8e53877baf2993fb3073b2fc9f69790ca6a732eb4bfea",
+                "sha256:cf60dd2696b457b710dd40bf17ad269d5f5457b96442f7f85722bdb16fa6c899",
+                "sha256:d1ba00ae33be84066cfbe7361d4e04dec78445b2b88bdb734d0d1cbab916025a",
+                "sha256:d39fc4817fd67b3915256af5dda75fd4ee10621a3d484524487e33416c6f3543",
+                "sha256:d766a4f0e5aa1ba056ec3496243150698dc0481902e2b8559314368717be82b1",
+                "sha256:dbf364b4c5e7bae9250528167dfe40219b62e2d573c854d74be213e1e52069f7",
+                "sha256:dd19608788b50eed889e13a5d71d832edc34fc9dfce606f66e8f9f917eef910d",
+                "sha256:e013b07ba1c748dacc2a80e69a46286ff145935f260eb8c72df7185bf048f502",
+                "sha256:e5d2b9be5b0693cf21eb4ce0ec8d211efb43966f6657807f6859aab3814f946b",
+                "sha256:e5ff52d790c7e1628241ffbcaeb33e07d14b007b6eb00a19320c7b8a7024c040",
+                "sha256:e75a2ad7b647fd8046d58c3132d7eaf31b12d8a53c0e4b21fa9c4d23d6ee6d3c",
+                "sha256:e7ac22a0bb2c7c49f441f7a6d46c9c80d96e56f5a8bc6972529ed43c8b694e27",
+                "sha256:ed2144b8a78f9d94d9515963ed273d620e07846acd5d4b0a642d4849e8d91a0c",
+                "sha256:f017a61399f13aa6d1039f75cd467be388d157cd81f1a119b9d9a68ba6f2830d",
+                "sha256:f1d8a2a57b47142b10374902777e798784abf400a004b14f1b0b9eaf1e528ba4",
+                "sha256:f2d32f95922927186c6dbc8bc60df0d186b6edb828d299ab10898ef3f40052fe",
+                "sha256:f319bae0321bc838e205bf9e5bc28f0a3165f30c203b610f17ab5552cff90323",
+                "sha256:f3c38e4e5ccbdc9198aecc766cedbb134b2d89bf64533973678dfcf07effd883",
+                "sha256:f9983d01d7705b2d1f7a95e10bbe4091fabc03a46881a256c2787637b087003f",
+                "sha256:fa260de59dfb143af06dcf30c2be0b200bed2a73737a8a59248fcb9fa601ef0f"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4' and python_version < '4'",
-            "version": "==5.5"
+            "markers": "python_version >= '3.9'",
+            "version": "==7.8.0"
         },
         "expects": {
             "hashes": [
@@ -95,34 +106,34 @@
         },
         "mamba": {
             "hashes": [
-                "sha256:75cfc6dfd287dcccaf86dd753cf48e0a7337487c7c3fafda05a6a67ded6da496"
+                "sha256:4dcf69e9a53e78d4aa5ec3dee0bb2c65f02ea68a6b62c4275653d7170b8f5fe2"
             ],
             "index": "pypi",
-            "version": "==0.11.2"
+            "version": "==0.11.3"
         },
         "path": {
             "hashes": [
-                "sha256:2de925e8d421f93bcea80d511b81accfb6a7e6b249afa4a5559557b0cf817097",
-                "sha256:340054c5bb459fc9fd40e7eb6768c5989f3e599d18224238465b5333bc8faa7d"
+                "sha256:688e7ec254f07a1c25f5474662d4480c663a2c8c4eb15c0ba056d8ab81608d22",
+                "sha256:d41e05ed4fa1d4f6d702df3c1e0a1a255d7b544287432456455dc7c51e5f98e9"
             ],
-            "markers": "python_version >= '3.6'",
-            "version": "==16.2.0"
+            "markers": "python_version >= '3.9'",
+            "version": "==17.1.0"
         },
         "path.py": {
             "hashes": [
                 "sha256:8d885e8b2497aed005703d94e0fd97943401f035e42a136810308bff034529a8",
                 "sha256:a43e82eb2c344c3fd0b9d6352f6b856f40b8b7d3d65cc05978b42c3715668496"
             ],
-            "index": "pypi",
+            "markers": "python_version >= '3.5'",
             "version": "==12.5.0"
         },
         "pexpect": {
             "hashes": [
-                "sha256:0b48a55dcb3c05f3329815901ea4fc1537514d6ba867a152b581d69ae3710937",
-                "sha256:fc65a43959d153d0114afe13997d439c22823a27cefceb5ff35c2178c6784c0c"
+                "sha256:7236d1e080e4936be2dc3e326cec0af72acf9212a7e1d060210e70a47e253523",
+                "sha256:ee7d41123f3c9911050ea2c2dac107568dc43b2d3b0c7557a33212c398ead30f"
             ],
             "index": "pypi",
-            "version": "==4.8.0"
+            "version": "==4.9.0"
         },
         "ptyprocess": {
             "hashes": [
diff --git a/builder/devenv-vncserver b/builder/devenv-vncserver
index 1ec401f..34b446b 100755
--- a/builder/devenv-vncserver
+++ b/builder/devenv-vncserver
@@ -3,7 +3,7 @@
 set -e
 
 default_os=ubuntu
-default_os_codename=focal
+default_os_codename=jammy
 
 cd "$(dirname "$0")/.."
 . ./builder/os_ver_cli.sh
diff --git a/builder/dockerfile.ubuntu_focal.specs.test b/builder/dockerfile.ubuntu_jammy.specs.test
similarity index 97%
rename from builder/dockerfile.ubuntu_focal.specs.test
rename to builder/dockerfile.ubuntu_jammy.specs.test
index 414aebc..ed59899 100644
--- a/builder/dockerfile.ubuntu_focal.specs.test
+++ b/builder/dockerfile.ubuntu_jammy.specs.test
@@ -1,4 +1,4 @@
-FROM ubuntu:focal
+FROM ubuntu:jammy
 
 ENV DEBIAN_FRONTEND=noninteractive
 
diff --git a/builder/dockerfile.ubuntu_focal.vncserver_devenv.test b/builder/dockerfile.ubuntu_jammy.vncserver_devenv.test
similarity index 99%
rename from builder/dockerfile.ubuntu_focal.vncserver_devenv.test
rename to builder/dockerfile.ubuntu_jammy.vncserver_devenv.test
index 103a6f2..975a97c 100644
--- a/builder/dockerfile.ubuntu_focal.vncserver_devenv.test
+++ b/builder/dockerfile.ubuntu_jammy.vncserver_devenv.test
@@ -1,4 +1,4 @@
-FROM ubuntu:focal
+FROM ubuntu:jammy
 
 ENV DEBIAN_FRONTEND=noninteractive
 ENV VNC_PORT 8443
diff --git a/builder/test-vncserver b/builder/test-vncserver
index 3263943..14b4fc0 100755
--- a/builder/test-vncserver
+++ b/builder/test-vncserver
@@ -3,7 +3,7 @@
 set -e
 
 default_os=ubuntu
-default_os_codename=focal
+default_os_codename=jammy
 
 . ./builder/os_ver_cli.sh