--- a/taskcluster/ci/test/mochitest.yml
+++ b/taskcluster/ci/test/mochitest.yml
@@ -44,17 +44,16 @@ mochitest:
             android.*: 24
             linux.*/debug: 16
             linux64-asan/opt: 10
             linux64-.*cov/opt: 10
             windows10-64-ccov/debug: 10
             default: 5
     e10s:
         by-test-platform:
-            linux64-jsdcov/opt: false
             linux32/debug: both
             default: true
     max-run-time:
         by-test-platform:
             android.*: 7200
             default: 5400
     allow-software-gl-layers: false
     tier:
@@ -98,20 +97,16 @@ mochitest-browser-chrome:
             default: mochitest/browser-chrome-chunked
     treeherder-symbol: M(bc)
     loopback-video: true
     chunks:
         by-test-platform:
             linux.*/debug: 16
             linux64-asan/opt: 16
             default: 7
-    e10s:
-        by-test-platform:
-            linux64-jsdcov/opt: false
-            default: true
     max-run-time:
         by-test-platform:
             linux64-.*cov/opt: 7200
             windows10-64-ccov/debug: 7200
             linux.*/debug: 5400
             default: 3600
     mozharness:
         mochitest-flavor: browser
@@ -238,20 +233,16 @@ mochitest-devtools-chrome:
     run-on-projects:
         by-test-platform:
             linux64-jsdcov/opt: ['try']  # jsdcov only on try, Bug 1442823
             default: built-projects
     chunks:
         by-test-platform:
             windows10-64-ccov/debug: 10
             default: 8
-    e10s:
-        by-test-platform:
-            linux64-jsdcov/opt: false
-            default: true
     mozharness:
         mochitest-flavor: chrome
         chunked: true
     instance-size:
         by-test-platform:
             linux64-asan/opt: xlarge  # runs out of memory on default/m3.large
             default: default
     # Bug 1296086: high number of intermittents observed with software GL and large instances

--- a/taskcluster/ci/test/reftest.yml
+++ b/taskcluster/ci/test/reftest.yml
@@ -68,20 +68,16 @@ jsreftest:
             android.*: 40
             windows.*: 2
             windows10-64-ccov/debug: 5
             linux64-ccov/.*: 5
             linux64-qr/.*: 4
             linux32/debug: 5
             macosx.*: 2
             default: 3
-    e10s:
-        by-test-platform:
-            linux64-jsdcov/opt: false
-            default: true
     max-run-time:
         by-test-platform:
             android.*: 7200
             windows10-64-ccov/debug: 7200
             default: 3600
     tier:
         by-test-platform:
             linux64-qr/.*: 1
@@ -164,20 +160,16 @@ reftest-no-accel:
         by-test-platform:
             windows10.*: []
             default: built-projects
     chunks:
         by-test-platform:
             macosx.*: 1
             windows.*: 4
             default: 8
-    e10s:
-        by-test-platform:
-            linux64-jsdcov/opt: false
-            default: true
     mozharness:
         chunked:
             by-test-platform:
                 windows10-64.*/opt: false
                 macosx.*: false
                 default: true
     tier:
         by-test-platform: