--- a/taskcluster/ci/test/test-platforms.yml
+++ b/taskcluster/ci/test/test-platforms.yml
@@ -35,58 +35,52 @@ linux32-devedition/opt:
         -  linux32-tests
         -  linux32-opt-tests
 
 linux64/debug:
     build-platform: linux64/debug
     test-sets:
         - common-tests
         - web-platform-tests
-        - headless
 linux64/opt:
     build-platform: linux64/opt
     test-sets:
         - common-tests
         - web-platform-tests
         - opt-only-tests
         - desktop-screenshot-capture
         - talos
         - awsy
-        - headless
 linux64-nightly/opt:
     build-platform: linux64-nightly/opt
     test-sets:
         - common-tests
         - web-platform-tests
         - opt-only-tests
         - desktop-screenshot-capture
-        - headless
 linux64-devedition/opt:
     build-platform: linux64-devedition-nightly/opt
     test-sets:
         - common-tests
         - web-platform-tests
         - opt-only-tests
         - desktop-screenshot-capture
-        - headless
 
 # TODO: use 'pgo' and 'asan' labels here, instead of -pgo/opt
 linux64-pgo/opt:
     build-platform: linux64-pgo/opt
     test-sets:
         - common-tests
         - web-platform-tests
         - talos
-        - headless
 
 linux64-asan/opt:
     build-platform: linux64-asan/opt
     test-sets:
         - common-tests
-        - headless
 
 # Stylo builds only run a subset of tests for the moment. So give them
 # their own test set.
 linux64-stylo/debug:
     build-platform: linux64/debug
     test-sets:
         - stylo-tests
 linux64-stylo/opt:
@@ -118,104 +112,93 @@ linux64-qr/debug:
 
 linux64-ccov/opt:
     build-platform: linux64-ccov/opt
     test-sets:
         - common-tests
         - web-platform-tests
         - awsy
         - talos
-        - headless
 linux64-jsdcov/opt:
     build-platform: linux64-jsdcov/opt
     test-sets:
         - jsdcov-code-coverage-tests
 
 ##
 # Windows platforms (matching /windows.*/)
 
 # win32
 windows7-32/debug:
     build-platform: win32/debug
     test-sets:
-        - headless
         - windows-tests
 windows7-32/opt:
     build-platform: win32/opt
     test-sets:
         - awsy
         - desktop-screenshot-capture
-        - headless
         - windows-talos
         - windows-tests
 
 windows7-32-pgo/opt:
     build-platform: win32-pgo/opt
     test-sets:
         - awsy
         - desktop-screenshot-capture
-        - headless
         - windows-tests
         - windows-talos
 
 windows7-32-nightly/opt:
     build-platform: win32-nightly/opt
     test-sets:
         - awsy
         - desktop-screenshot-capture
-        - headless
         - windows-tests
 
 windows7-32-devedition/opt:
     build-platform: win32-devedition/opt
     test-sets:
         - awsy
         - desktop-screenshot-capture
-        - headless
         - windows-tests
 
 # win64
 windows10-64/debug:
     build-platform: win64/debug
     test-sets:
-        - headless
         - windows-tests
 
 windows10-64/opt:
     build-platform: win64/opt
     test-sets:
         - awsy
         - desktop-screenshot-capture
-        - headless
         - windows-talos
         - windows-tests
 
 windows10-64-pgo/opt:
     build-platform: win64-pgo/opt
     test-sets:
         - awsy
         - desktop-screenshot-capture
-        - headless
         - windows-talos
         - windows-tests
 
 windows10-64-nightly/opt:
     build-platform: win64-nightly/opt
     test-sets:
         - awsy
         - desktop-screenshot-capture
-        - headless
         - windows-tests
 
 windows10-64-devedition/opt:
     build-platform: win64-devedition/opt
     test-sets:
         - awsy
         - desktop-screenshot-capture
-        - headless
         - windows-tests
 
 windows10-64-asan/opt:
     build-platform: win64-asan/opt
     test-sets:
         - common-tests
 
 # Windows8 tests; all via BBB

--- a/taskcluster/ci/test/test-sets.yml
+++ b/taskcluster/ci/test/test-sets.yml
@@ -19,16 +19,17 @@ common-tests:
     - cppunit
     - crashtest
     - firefox-ui-functional-local
     - firefox-ui-functional-remote
     - gtest
     - jittest
     - jsreftest
     - marionette
+    - marionette-headless
     - mochitest
     - mochitest-a11y
     - mochitest-browser-chrome
     - mochitest-chrome
     - mochitest-clipboard
     - mochitest-devtools-chrome
     - mochitest-gpu
     - mochitest-jetpack
@@ -59,19 +60,16 @@ talos:
     - talos-svgr
     - talos-tp5o
     - talos-perf-reftest
     - talos-perf-reftest-singletons
 
 awsy:
     - awsy
 
-headless:
-    - marionette-headless
-
 ##
 # Limited test sets for specific platforms
 
 stylo-tests:
     - cppunit
     - crashtest
     - reftest
     - reftest-stylo
@@ -109,16 +107,17 @@ windows-tests:
     - cppunit
     - crashtest
     - firefox-ui-functional-local
     - firefox-ui-functional-remote
     - gtest
     - jittest
     - jsreftest
     - marionette
+    - marionette-headless
     - mochitest
     - mochitest-a11y
     - mochitest-browser-chrome
     - mochitest-chrome
     - mochitest-clipboard
     - mochitest-devtools-chrome
     - mochitest-gpu
     - mochitest-jetpack
@@ -151,16 +150,17 @@ macosx64-tests:
     - cppunit
     - crashtest
     - firefox-ui-functional-local
     - firefox-ui-functional-remote
     - gtest
     - jittest
     - jsreftest
     - marionette
+    - marionette-headless
     - mochitest
     - mochitest-a11y
     - mochitest-browser-chrome
     - mochitest-chrome
     - mochitest-clipboard
     - mochitest-devtools-chrome
     - mochitest-gpu
     - mochitest-jetpack