message: Github CI: enforce Ubuntu 20.04 instead of ubuntu-latest, which isn't latest LTS nor latest release
diff: @@ -13,9 +13,9 @@ on:
  - master
  jobs:
  - ubuntu_latest:
  - name: "Ubuntu Linux"
  - runs-on: ubuntu-latest
  + ubuntu_2004:
  + name: "Ubuntu Linux 20.04"
  + runs-on: ubuntu-20.04
  steps:
  - uses: actions/checkout@v1
  - name: "initialize sub modules"
  @@ -45,9 +45,9 @@ jobs:
  - name: "test: libterminal"
  run: ./build/src/terminal/terminal_test
  - ubuntu_latest_qt_kde:
  - name: "Ubuntu Linux (with KWin support)"
  - runs-on: ubuntu-latest
  + ubuntu_2004_qt_kde:
  + name: "Ubuntu Linux 20.04 (with KWin support)"
  + runs-on: ubuntu-20.04
  steps:
  - uses: actions/checkout@v1
  - name: "initialize sub modules"
  