diff --git a/etc/ci/buildbot_steps.yml b/etc/ci/buildbot_steps.yml
index dde95a79444..40da34c3305 100644
--- a/etc/ci/buildbot_steps.yml
+++ b/etc/ci/buildbot_steps.yml
@@ -79,14 +79,14 @@ mac-nightly:
 linux-rel-intermittent:
   - ./mach clean-nightlies --keep 3 --force
   - ./mach clean-cargo-cache --keep 3 --force
-  - ./mach clean
+  - ./etc/ci/clean_build_artifacts.sh
   - ./mach build --release
   - ./etc/ci/check_intermittents.sh --log-raw intermittents.log
 
 linux-rel-nogate:
   - ./mach clean-nightlies --keep 3 --force
   - ./mach clean-cargo-cache --keep 3 --force
-  - ./mach clean
+  - ./etc/ci/clean_build_artifacts.sh
   - ./mach build --release
   - python ./etc/ci/chaos_monkey_test.py
   - env RUSTFLAGS= bash ./etc/ci/mutation_test.sh
@@ -104,7 +104,7 @@ linux-dev:
   commands:
     - ./mach clean-nightlies --keep 3 --force
     - ./mach clean-cargo-cache --keep 3 --force
-    - ./mach clean
+    - ./etc/ci/clean_build_artifacts.sh
     - ./mach test-tidy --no-progress --all
     - ./mach test-tidy --no-progress --self-test
     - ./mach build --dev
@@ -124,7 +124,7 @@ linux-rel-wpt:
   commands:
     - ./mach clean-nightlies --keep 3 --force
     - ./mach clean-cargo-cache --keep 3 --force
-    - ./mach clean
+    - ./etc/ci/clean_build_artifacts.sh
     - ./mach build --release --with-debug-assertions
     - ./mach test-wpt-failure
     - ./mach test-wpt --release --processes 24 --total-chunks 2 --this-chunk 1 --log-raw test-wpt.log --log-errorsummary wpt-errorsummary.log --always-succeed
@@ -138,7 +138,7 @@ linux-rel-css:
   commands:
     - ./mach clean-nightlies --keep 3 --force
     - ./mach clean-cargo-cache --keep 3 --force
-    - ./mach clean
+    - ./etc/ci/clean_build_artifacts.sh
     - ./mach build --release --with-debug-assertions
     - ./mach test-wpt --release --processes 24 --total-chunks 2 --this-chunk 2 --log-raw test-wpt.log --log-errorsummary wpt-errorsummary.log --always-succeed
     - ./mach filter-intermittents wpt-errorsummary.log --log-intermittents intermittents.log --log-filteredsummary filtered-wpt-errorsummary.log --tracker-api default --reporter-api default
@@ -150,7 +150,7 @@ linux-rel-css:
 linux-nightly:
   - ./mach clean-nightlies --keep 3 --force
   - ./mach clean-cargo-cache --keep 3 --force
-  - ./mach clean
+  - ./etc/ci/clean_build_artifacts.sh
   - ./mach build --release
   - ./mach package --release
   - ./mach upload-nightly linux
diff --git a/etc/ci/clean_build_artifacts.sh b/etc/ci/clean_build_artifacts.sh
new file mode 100755
index 00000000000..f3d7d725060
--- /dev/null
+++ b/etc/ci/clean_build_artifacts.sh
@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+rm -rf target/{debug,release,doc,geckolib}