diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index aa469bc2bfe500..96382a746df08e 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -244,26 +244,21 @@ jobs:
     name: ${{ matrix.name }}
     needs: syntax
     runs-on: ${{ matrix.runs-on }}
-    container: ${{ matrix.container }}
     strategy:
       matrix:
         include:
           - name: tests (online)
             test-flags: --online --coverage
             runs-on: ubuntu-latest
-            container: ghcr.io/homebrew/brew:master
           - name: tests (generic OS)
             test-flags: --generic --coverage
             runs-on: ubuntu-latest
-            container: ghcr.io/homebrew/brew:master
           - name: tests (Ubuntu 22.04)
             test-flags: --coverage
             runs-on: ubuntu-latest
-            container: ghcr.io/homebrew/ubuntu22.04:master
           - name: tests (Ubuntu 20.04)
             test-flags: --coverage
             runs-on: ubuntu-latest
-            container: ghcr.io/homebrew/ubuntu20.04
           - name: tests (macOS 13 x86_64)
             test-flags: --coverage
             runs-on: macos-13
@@ -275,7 +270,10 @@ jobs:
         id: set-up-homebrew
         uses: Homebrew/actions/setup-homebrew@master
         with:
-          core: true
+          # We only test needs_homebrew_core tests on macOS because
+          # homebrew/core is not available by default on GitHub-hosted Ubuntu
+          # runners, and it's expensive to tap it.
+          core: ${{ runner.os == 'macOS' }}
           cask: false
           test-bot: false