diff --git a/.github/workflows/arch.yml b/.github/workflows/arch.yml
new file mode 100644
index 0000000..9e03118
--- /dev/null
+++ b/.github/workflows/arch.yml
@@ -0,0 +1,45 @@
+name: archlinux
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    container:
+      image: archlinux:latest
+    strategy:
+      matrix:
+        buildtype: [Debug, Release]
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 3
+      - run: >
+          pacman -Sy --noconfirm
+          base-devel
+          git
+          boost-libs boost
+          qt5-base qt5-tools
+          poppler-qt5
+          cmake
+          xorg-server-xvfb
+      - run: >
+          cmake -B build/
+          -DCMAKE_VERBOSE_MAKEFILE=ON
+          -DUsePrerenderedPDF=ON
+          -DCodeCoverage=ON
+          -DWarningAsError=ON
+          -DCMAKE_BUILD_TYPE=${{matrix.buildtype}}
+          .
+      - run: cmake --build build/
+      - name: run tests within xvfb
+        working-directory: build/
+        run: >
+          xvfb-run -a -s '-screen 0 1920x1080x24 -screen 1 1920x1200x24'
+          ctest --output-on-failure --timeout 60
+      - name: upload coverage
+        run: bash <(curl -s https://codecov.io/bash)
diff --git a/.github/workflows/clang.yml b/.github/workflows/clang.yml
index 22d5903..0864071 100644
--- a/.github/workflows/clang.yml
+++ b/.github/workflows/clang.yml
@@ -34,6 +34,7 @@ jobs:
           -DCMAKE_VERBOSE_MAKEFILE=ON
           -DUsePrerenderedPDF=ON
           -DCodeCoverage=ON
+          -DWarningAsError=ON
           -DCMAKE_BUILD_TYPE=${{matrix.buildtype}}
           .
       - run: cmake --build build/
diff --git a/.github/workflows/osx.yml b/.github/workflows/osx.yml
index e5cda8a..a6eb471 100644
--- a/.github/workflows/osx.yml
+++ b/.github/workflows/osx.yml
@@ -18,6 +18,8 @@ jobs:
       PKG_CONFIG_PATH: /usr/local/opt/poppler-qt5/lib/pkgconfig:/usr/local/opt/poppler-qt5/share/pkgconfig
     steps:
       - uses: actions/checkout@v3
+        with:
+          fetch-depth: 3
       - run: brew install boost
       - run: brew install poppler-qt5
       - name: cmake -B build/
@@ -28,6 +30,7 @@ jobs:
           -DCodeCoverage=ON
           -DCMAKE_BUILD_TYPE=${{matrix.buildtype}}
           -DRunDualScreenTests=OFF
+          -DWarningAsError=ON
           .
       - run: cmake --build build/
       - run: ctest --output-on-failure --timeout 60
diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
index 4c09cfb..0ab9287 100644
--- a/.github/workflows/ubuntu.yml
+++ b/.github/workflows/ubuntu.yml
@@ -11,10 +11,12 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-          os: [ ubuntu-18.04, ubuntu-20.04, ubuntu-22.04 ]
+          os: [ ubuntu-20.04, ubuntu-22.04 ]
           buildtype: [ Debug, Release ]
     steps:
       - uses: actions/checkout@v3
+        with:
+          fetch-depth: 3
       - run: sudo apt-get update
       - name: Install build deps
         run: >
@@ -31,6 +33,7 @@ jobs:
           -DCMAKE_VERBOSE_MAKEFILE=ON
           -DUsePrerenderedPDF=ON
           -DCodeCoverage=ON
+          -DWarningAsError=ON
           -DCMAKE_BUILD_TYPE=${{matrix.buildtype}}
           .
       - run: cmake --build build/
diff --git a/dspdfviewer.cpp b/dspdfviewer.cpp
index b963bec..85e8279 100644
--- a/dspdfviewer.cpp
+++ b/dspdfviewer.cpp
@@ -47,7 +47,7 @@ DSPDFViewer::DSPDFViewer(const RuntimeConfiguration& r):
  renderFactory(r),
  m_pagenumber(0),
  audienceWindow(1,   r.useFullPage()                 ? PagePart::FullPage : PagePart::LeftHalf , false, r, WindowRole::AudienceWindow),
- secondaryWindow(0, (r.useFullPage() | r.duplicate())? PagePart::FullPage : PagePart::RightHalf, true , r, WindowRole::PresenterWindow, r.useSecondScreen())
+ secondaryWindow(0, (r.useFullPage() || r.duplicate())? PagePart::FullPage : PagePart::RightHalf, true , r, WindowRole::PresenterWindow, r.useSecondScreen())
 {
   DEBUGOUT << tr("Starting constructor") ;
 
@@ -307,7 +307,7 @@ RenderingIdentifier DSPDFViewer::toRenderIdent(unsigned int pageNumber, const PD
 
 RenderingIdentifier DSPDFViewer::toThumbnailRenderIdent(unsigned int pageNumber, PDFViewerWindow& window)
 {
-  QSize newSize = window.getPreviewImageSize();;
+  QSize newSize = window.getPreviewImageSize();
   static QSize thumbnailSize;
   if ( thumbnailSize != newSize ) {
     DEBUGOUT << "Thumbnail size changed from" << thumbnailSize << "to" << newSize;