--- a/browser/config/mozconfigs/linux64/code-coverage
+++ b/browser/config/mozconfigs/linux64/code-coverage
@@ -1,14 +1,13 @@
 . "$topsrcdir/browser/config/mozconfigs/linux64/nightly"
 
 TOOLTOOL_DIR=${TOOLTOOL_DIR:-$topsrcdir}
 
 ac_add_options --disable-install-strip
 ac_add_options --disable-elf-hack
-ac_add_options --enable-debug
 ac_add_options --disable-sandbox
 ac_add_options --disable-profiling
 ac_add_options --enable-coverage
 
 export CFLAGS="--coverage"
 export CXXFLAGS="--coverage"
 export LDFLAGS="--coverage -L$TOOLTOOL_DIR/gtk3/usr/local/lib"

new file mode 100644
--- /dev/null
+++ b/browser/config/mozconfigs/linux64/code-coverage-debug
@@ -0,0 +1,3 @@
+. "$topsrcdir/browser/config/mozconfigs/linux64/code-coverage"
+
+ac_add_options --enable-debug
\ No newline at end of file

--- a/browser/config/mozconfigs/linux64/code-coverage-opt
+++ b/browser/config/mozconfigs/linux64/code-coverage-opt
@@ -1,13 +1,2 @@
-. "$topsrcdir/browser/config/mozconfigs/linux64/nightly"
-
-TOOLTOOL_DIR=${TOOLTOOL_DIR:-$topsrcdir}
+. "$topsrcdir/browser/config/mozconfigs/linux64/code-coverage"
 
-ac_add_options --disable-install-strip
-ac_add_options --disable-elf-hack
-ac_add_options --disable-sandbox
-ac_add_options --disable-profiling
-ac_add_options --enable-coverage
-
-export CFLAGS="--coverage"
-export CXXFLAGS="--coverage"
-export LDFLAGS="--coverage -L$TOOLTOOL_DIR/gtk3/usr/local/lib"

--- a/taskcluster/ci/build/linux.yml
+++ b/taskcluster/ci/build/linux.yml
@@ -853,32 +853,33 @@ linux64-ccov/debug:
     run:
         using: mozharness
         actions: [get-secrets build check-test update]
         config:
             - builds/releng_base_firefox.py
             - builds/releng_base_linux_64_builds.py
         script: "mozharness/scripts/fx_desktop_build.py"
         secrets: true
-        custom-build-variant-cfg: code-coverage
+        custom-build-variant-cfg: code-coverage-debug
         tooltool-downloads: public
         need-xvfb: true
     toolchains:
         - linux64-clang-4
         - linux64-rust
         - linux64-gcc
 
 linux64-ccov/opt:
     description: "Linux64-CCov Opt"
     index:
         product: firefox
         job-name: linux64-ccov-opt
     treeherder:
         platform: linux64-ccov/opt
-        symbol: B
+        symbol: Bo
+        tier: 2
     run-on-projects: []
     worker-type: aws-provisioner-v1/gecko-{level}-b-linux
     worker:
         max-run-time: 36000
     run:
         using: mozharness
         actions: [get-secrets build check-test update]
         config:

deleted file mode 100644
--- a/testing/mozharness/configs/builds/releng_sub_linux_configs/64_code_coverage.py
+++ /dev/null
@@ -1,28 +0,0 @@
-import os
-
-config = {
-    'default_actions': [
-        'clobber',
-        'build',
-        'check-test',
-        'update',  # decided by query_is_nightly()
-    ],
-    'stage_platform': 'linux64-ccov',
-    #### 64 bit build specific #####
-    'env': {
-        'MOZBUILD_STATE_PATH': os.path.join(os.getcwd(), '.mozbuild'),
-        'DISPLAY': ':2',
-        'HG_SHARE_BASE_DIR': '/builds/hg-shared',
-        'MOZ_OBJDIR': '%(abs_obj_dir)s',
-        'TINDERBOX_OUTPUT': '1',
-        'TOOLTOOL_CACHE': '/builds/tooltool_cache',
-        'TOOLTOOL_HOME': '/builds',
-        'MOZ_CRASHREPORTER_NO_REPORT': '1',
-        'LC_ALL': 'C',
-        ## 64 bit specific
-        'PATH': '/usr/local/bin:/bin:\
-/usr/bin:/usr/local/sbin:/usr/sbin:/sbin',
-    },
-    'mozconfig_variant': 'code-coverage',
-    #######################
-}

new file mode 100644
--- /dev/null
+++ b/testing/mozharness/configs/builds/releng_sub_linux_configs/64_code_coverage_debug.py
@@ -0,0 +1,28 @@
+import os
+
+config = {
+    'default_actions': [
+        'clobber',
+        'build',
+        'check-test',
+        'update',  # decided by query_is_nightly()
+    ],
+    'stage_platform': 'linux64-ccov',
+    #### 64 bit build specific #####
+    'env': {
+        'MOZBUILD_STATE_PATH': os.path.join(os.getcwd(), '.mozbuild'),
+        'DISPLAY': ':2',
+        'HG_SHARE_BASE_DIR': '/builds/hg-shared',
+        'MOZ_OBJDIR': '%(abs_obj_dir)s',
+        'TINDERBOX_OUTPUT': '1',
+        'TOOLTOOL_CACHE': '/builds/tooltool_cache',
+        'TOOLTOOL_HOME': '/builds',
+        'MOZ_CRASHREPORTER_NO_REPORT': '1',
+        'LC_ALL': 'C',
+        ## 64 bit specific
+        'PATH': '/usr/local/bin:/bin:\
+/usr/bin:/usr/local/sbin:/usr/sbin:/sbin',
+    },
+    'mozconfig_variant': 'code-coverage-debug',
+    #######################
+}

--- a/testing/mozharness/mozharness/mozilla/building/buildbase.py
+++ b/testing/mozharness/mozharness/mozilla/building/buildbase.py
@@ -415,17 +415,17 @@ class BuildOptionParser(object):
         'cross-noopt-debug': 'builds/releng_sub_%s_configs/%s_cross_noopt_debug.py',
         'cross-fuzzing-asan': 'builds/releng_sub_%s_configs/%s_cross_fuzzing_asan.py',
         'cross-artifact': 'builds/releng_sub_%s_configs/%s_cross_artifact.py',
         'debug': 'builds/releng_sub_%s_configs/%s_debug.py',
         'fuzzing-debug': 'builds/releng_sub_%s_configs/%s_fuzzing_debug.py',
         'asan-and-debug': 'builds/releng_sub_%s_configs/%s_asan_and_debug.py',
         'asan-tc-and-debug': 'builds/releng_sub_%s_configs/%s_asan_tc_and_debug.py',
         'stat-and-debug': 'builds/releng_sub_%s_configs/%s_stat_and_debug.py',
-        'code-coverage': 'builds/releng_sub_%s_configs/%s_code_coverage.py',
+        'code-coverage-debug': 'builds/releng_sub_%s_configs/%s_code_coverage_debug.py',
         'code-coverage-opt': 'builds/releng_sub_%s_configs/%s_code_coverage_opt.py',
         'source': 'builds/releng_sub_%s_configs/%s_source.py',
         'noopt-debug': 'builds/releng_sub_%s_configs/%s_noopt_debug.py',
         'api-16-gradle-dependencies': 'builds/releng_sub_%s_configs/%s_api_16_gradle_dependencies.py',
         'api-16': 'builds/releng_sub_%s_configs/%s_api_16.py',
         'api-16-artifact': 'builds/releng_sub_%s_configs/%s_api_16_artifact.py',
         'api-16-debug': 'builds/releng_sub_%s_configs/%s_api_16_debug.py',
         'api-16-debug-artifact': 'builds/releng_sub_%s_configs/%s_api_16_debug_artifact.py',