diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index bb4efadc..76f5f856 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -98,6 +98,11 @@ jobs:
     - name: Install packages
       if: startswith(matrix.config.os, 'ubuntu')
       run: sudo apt install qt5-default libqt5svg5-dev
+    
+    # Ubuntu 18.04 only:
+    - name: Install g++-8
+      if: matrix.config.os == 'ubuntu-18.04'
+      run: sudo apt install g++-8
 
     # All:
     - name: Create Build Environment
@@ -242,6 +247,11 @@ jobs:
       if: startswith(matrix.config.os, 'ubuntu')
       run: sudo apt install liblua5.3-dev lcov libarchive-dev
 
+    # Ubuntu 18.04 only:
+    - name: Install g++-8
+      if: matrix.config.os == 'ubuntu-18.04'
+      run: sudo apt install g++-8
+
     # All:
     - name: Create Build Environment
       # Some projects don't allow in-source building, so create a separate build directory