diff --git a/resources/celerity/map.php b/resources/celerity/map.php
--- a/resources/celerity/map.php
+++ b/resources/celerity/map.php
@@ -9,10 +9,14 @@
   'names' => array(
     'conpherence.pkg.css' => '2f25eb4f',
     'conpherence.pkg.js' => '020aebcf',
+<<<<<<< HEAD
     'core.pkg.css' => 'c753df75',
+=======
+    'core.pkg.css' => '77d64402',
+>>>>>>> 67b4f957d1 (Revert "Added cross-platform default fonts")
     'core.pkg.js' => '2eeda9e0',
     'dark-console.pkg.js' => '187792c2',
-    'differential.pkg.css' => '2431def2',
+    'differential.pkg.css' => '6d3700f0',
     'differential.pkg.js' => '46fcb3af',
     'diffusion.pkg.css' => '42c75c37',
     'diffusion.pkg.js' => '78c9885d',
@@ -44,7 +48,7 @@
     'rsrc/css/application/base/standard-page-view.css' => 'e08c7462',
     'rsrc/css/application/conduit/conduit-api.css' => 'ce2cfc41',
     'rsrc/css/application/config/config-options.css' => '16c920ae',
-    'rsrc/css/application/config/config-template.css' => 'e689dbbd',
+    'rsrc/css/application/config/config-template.css' => '20babf50',
     'rsrc/css/application/config/setup-issue.css' => '93231115',
     'rsrc/css/application/config/unhandled-exception.css' => '9ecfc00d',
     'rsrc/css/application/conpherence/color.css' => 'b17746b0',
@@ -62,9 +66,9 @@
     'rsrc/css/application/diff/diff-tree-view.css' => 'e2d3e222',
     'rsrc/css/application/diff/inline-comment-summary.css' => '81eb368d',
     'rsrc/css/application/differential/add-comment.css' => '7e5900d9',
-    'rsrc/css/application/differential/changeset-view.css' => '360630ff',
+    'rsrc/css/application/differential/changeset-view.css' => '1b0476bc',
     'rsrc/css/application/differential/core.css' => '7300a73e',
-    'rsrc/css/application/differential/phui-inline-comment.css' => 'a864426f',
+    'rsrc/css/application/differential/phui-inline-comment.css' => '9863a85e',
     'rsrc/css/application/differential/revision-comment.css' => '7dbc8d1d',
     'rsrc/css/application/differential/revision-history.css' => '237a2979',
     'rsrc/css/application/differential/revision-list.css' => '93d2df7d',
@@ -76,7 +80,7 @@
     'rsrc/css/application/feed/feed.css' => 'd8b6e3f8',
     'rsrc/css/application/files/global-drag-and-drop.css' => '1d2713a4',
     'rsrc/css/application/flag/flag.css' => '2b77be8d',
-    'rsrc/css/application/harbormaster/harbormaster.css' => 'cd0ce059',
+    'rsrc/css/application/harbormaster/harbormaster.css' => '9346e08b',
     'rsrc/css/application/herald/herald-test.css' => '7e7bbdae',
     'rsrc/css/application/herald/herald.css' => '648d39e2',
     'rsrc/css/application/maniphest/report.css' => '3d53188b',
@@ -100,16 +104,21 @@
     'rsrc/css/application/policy/policy-transaction-detail.css' => 'c02b8384',
     'rsrc/css/application/policy/policy.css' => 'ceb56a08',
     'rsrc/css/application/ponder/ponder-view.css' => 'b04bbaff',
-    'rsrc/css/application/project/project-card-view.css' => 'c1200da7',
+    'rsrc/css/application/project/project-card-view.css' => 'a9f2c2dd',
     'rsrc/css/application/project/project-triggers.css' => 'cd9c8bb9',
-    'rsrc/css/application/project/project-view.css' => '2f7caa20',
+    'rsrc/css/application/project/project-view.css' => '567858b3',
     'rsrc/css/application/search/application-search-view.css' => '0f7c06d8',
     'rsrc/css/application/search/search-results.css' => '9ea70ace',
     'rsrc/css/application/slowvote/slowvote.css' => '1694baed',
     'rsrc/css/application/tokens/tokens.css' => 'ce5a50bd',
     'rsrc/css/application/uiexample/example.css' => 'b4795059',
+<<<<<<< HEAD
     'rsrc/css/core/core.css' => 'b3a5928e',
     'rsrc/css/core/remarkup.css' => 'd91c2ee8',
+=======
+    'rsrc/css/core/core.css' => '531ad849',
+    'rsrc/css/core/remarkup.css' => 'b251d2e7',
+>>>>>>> 67b4f957d1 (Revert "Added cross-platform default fonts")
     'rsrc/css/core/syntax.css' => '548567f6',
     'rsrc/css/core/z-index.css' => 'ac3bfcd4',
     'rsrc/css/diviner/diviner-shared.css' => '4bd263b0',
@@ -123,7 +132,7 @@
     'rsrc/css/layout/phabricator-source-code-view.css' => 'e382316a',
     'rsrc/css/phui/button/phui-button-bar.css' => 'a4aa75c4',
     'rsrc/css/phui/button/phui-button-simple.css' => '1ff278aa',
-    'rsrc/css/phui/button/phui-button.css' => 'f9d0f9c8',
+    'rsrc/css/phui/button/phui-button.css' => '55025b10',
     'rsrc/css/phui/calendar/phui-calendar-day.css' => '9597d706',
     'rsrc/css/phui/calendar/phui-calendar-list.css' => 'ccd7e4e2',
     'rsrc/css/phui/calendar/phui-calendar-month.css' => 'cb758c42',
@@ -141,7 +150,7 @@
     'rsrc/css/phui/phui-big-info-view.css' => '362ad37b',
     'rsrc/css/phui/phui-box.css' => '5ed3b8cb',
     'rsrc/css/phui/phui-bulk-editor.css' => '374d5e30',
-    'rsrc/css/phui/phui-chart.css' => 'fe8f87a7',
+    'rsrc/css/phui/phui-chart.css' => '14df9ae3',
     'rsrc/css/phui/phui-cms.css' => '8c05c41e',
     'rsrc/css/phui/phui-comment-form.css' => '3c6679a3',
     'rsrc/css/phui/phui-comment-panel.css' => 'ec4e31c0',
@@ -154,7 +163,7 @@
     'rsrc/css/phui/phui-feed-story.css' => 'a0c05029',
     'rsrc/css/phui/phui-fontkit.css' => '1ec937e5',
     'rsrc/css/phui/phui-form-view.css' => '57edecb7',
-    'rsrc/css/phui/phui-form.css' => 'd1adb52c',
+    'rsrc/css/phui/phui-form.css' => '1f177cb7',
     'rsrc/css/phui/phui-formation-view.css' => 'd2dec8ed',
     'rsrc/css/phui/phui-head-thing.css' => 'd7f293df',
     'rsrc/css/phui/phui-header-view.css' => '36c86a58',
@@ -167,7 +176,7 @@
     'rsrc/css/phui/phui-left-right.css' => '68513c34',
     'rsrc/css/phui/phui-lightbox.css' => '4ebf22da',
     'rsrc/css/phui/phui-list.css' => 'ccf73664',
-    'rsrc/css/phui/phui-object-box.css' => 'fdffed5c',
+    'rsrc/css/phui/phui-object-box.css' => 'b8d7eea0',
     'rsrc/css/phui/phui-pager.css' => 'd022c7ad',
     'rsrc/css/phui/phui-pinboard-view.css' => '1f08f5d8',
     'rsrc/css/phui/phui-policy-section-view.css' => '139fdc64',
@@ -559,7 +568,7 @@
     'conpherence-transaction-css' => '3a3f5e7e',
     'd3' => '9d068042',
     'diff-tree-view-css' => 'e2d3e222',
-    'differential-changeset-view-css' => '360630ff',
+    'differential-changeset-view-css' => '1b0476bc',
     'differential-core-view-css' => '7300a73e',
     'differential-revision-add-comment-css' => '7e5900d9',
     'differential-revision-comment-css' => '7dbc8d1d',
@@ -578,7 +587,7 @@
     'fuel-map-css' => 'd6e31510',
     'fuel-menu-css' => '21f5d199',
     'global-drag-and-drop-css' => '1d2713a4',
-    'harbormaster-css' => 'cd0ce059',
+    'harbormaster-css' => '9346e08b',
     'herald-css' => '648d39e2',
     'herald-rule-editor' => '2633bef7',
     'herald-test-css' => '7e7bbdae',
@@ -770,7 +779,7 @@
     'phabricator-action-list-view-css' => '1b0085b2',
     'phabricator-busy' => '5202e831',
     'phabricator-content-source-view-css' => 'cdf0d579',
-    'phabricator-core-css' => 'b3a5928e',
+    'phabricator-core-css' => '531ad849',
     'phabricator-countdown-css' => 'bff8012f',
     'phabricator-darklog' => '3b869402',
     'phabricator-darkmessage' => '26cd4b73',
@@ -783,7 +792,7 @@
     'phabricator-diff-tree-view' => '5d83623b',
     'phabricator-drag-and-drop-file-upload' => '4370900d',
     'phabricator-draggable-list' => '0169e425',
-    'phabricator-fatal-config-template-css' => 'e689dbbd',
+    'phabricator-fatal-config-template-css' => '20babf50',
     'phabricator-favicon' => '7930776a',
     'phabricator-feed-css' => 'd8b6e3f8',
     'phabricator-file-upload' => '331676ea',
@@ -827,13 +836,13 @@
     'phui-box-css' => '5ed3b8cb',
     'phui-bulk-editor-css' => '374d5e30',
     'phui-button-bar-css' => 'a4aa75c4',
-    'phui-button-css' => 'f9d0f9c8',
+    'phui-button-css' => '55025b10',
     'phui-button-simple-css' => '1ff278aa',
     'phui-calendar-css' => 'f11073aa',
     'phui-calendar-day-css' => '9597d706',
     'phui-calendar-list-css' => 'ccd7e4e2',
     'phui-calendar-month-css' => 'cb758c42',
-    'phui-chart-css' => 'fe8f87a7',
+    'phui-chart-css' => '14df9ae3',
     'phui-cms-css' => '8c05c41e',
     'phui-comment-form-css' => '3c6679a3',
     'phui-comment-panel-css' => 'ec4e31c0',
@@ -846,7 +855,7 @@
     'phui-feed-story-css' => 'a0c05029',
     'phui-font-icon-base-css' => '303c9b87',
     'phui-fontkit-css' => '1ec937e5',
-    'phui-form-css' => 'd1adb52c',
+    'phui-form-css' => '1f177cb7',
     'phui-form-view-css' => '57edecb7',
     'phui-formation-view-css' => 'd2dec8ed',
     'phui-head-thing-view-css' => 'd7f293df',
@@ -858,12 +867,12 @@
     'phui-icon-view-css' => '084ac612',
     'phui-image-mask-css' => '62c7f4d2',
     'phui-info-view-css' => 'a10a909b',
-    'phui-inline-comment-view-css' => 'a864426f',
+    'phui-inline-comment-view-css' => '9863a85e',
     'phui-invisible-character-view-css' => 'c694c4a4',
     'phui-left-right-css' => '68513c34',
     'phui-lightbox-css' => '4ebf22da',
     'phui-list-view-css' => 'ccf73664',
-    'phui-object-box-css' => 'fdffed5c',
+    'phui-object-box-css' => 'b8d7eea0',
     'phui-oi-big-ui-css' => 'fa74cc35',
     'phui-oi-color-css' => 'b517bfa0',
     'phui-oi-drag-ui-css' => 'da15d3dc',
@@ -900,9 +909,9 @@
     'policy-edit-css' => '8794e2ed',
     'policy-transaction-detail-css' => 'c02b8384',
     'ponder-view-css' => 'b04bbaff',
-    'project-card-view-css' => 'c1200da7',
+    'project-card-view-css' => 'a9f2c2dd',
     'project-triggers-css' => 'cd9c8bb9',
-    'project-view-css' => '2f7caa20',
+    'project-view-css' => '567858b3',
     'setup-issue-css' => '93231115',
     'sprite-login-css' => '07052ee0',
     'sprite-tokens-css' => 'f1896dc5',
@@ -1055,6 +1064,9 @@
       'javelin-util',
       'phabricator-keyboard-shortcut-manager',
     ),
+    '1b0476bc' => array(
+      'phui-inline-comment-view-css',
+    ),
     '1b6acc2a' => array(
       'javelin-magical-init',
       'javelin-util',
@@ -1229,9 +1241,6 @@
       'aphront-typeahead-control-css',
       'phui-tag-view-css',
     ),
-    '360630ff' => array(
-      'phui-inline-comment-view-css',
-    ),
     '3829a3cf' => array(
       'javelin-behavior',
       'javelin-uri',
diff --git a/src/applications/celerity/postprocessor/CelerityDarkModePostprocessor.php b/src/applications/celerity/postprocessor/CelerityDarkModePostprocessor.php
--- a/src/applications/celerity/postprocessor/CelerityDarkModePostprocessor.php
+++ b/src/applications/celerity/postprocessor/CelerityDarkModePostprocessor.php
@@ -15,13 +15,13 @@
     return array(
 
       // Fonts
-      'basefont' => "13px -apple-system, system-ui, BlinkMacSystemFont, ".
-        "'Segoe UI', 'Segoe UI Emoji', 'Segoe UI Symbol', 'Lato', ".
-        "'Helvetica Neue', Helvetica, Arial, sans-serif",
+      'basefont' => "13px 'Segoe UI', 'Segoe UI Emoji', ".
+        "'Segoe UI Symbol', 'Lato', 'Helvetica Neue', ".
+        "Helvetica, Arial, sans-serif",
 
-      'fontfamily' => "-apple-system, system-ui, BlinkMacSystemFont, ".
-        "'Segoe UI', 'Segoe UI Emoji', 'Segoe UI Symbol', 'Lato', ".
-        "'Helvetica Neue', Helvetica, Arial, sans-serif",
+      'fontfamily' => "'Segoe UI', 'Segoe UI Emoji', ".
+        "'Segoe UI Symbol', 'Lato', 'Helvetica Neue', ".
+        "Helvetica, Arial, sans-serif",
 
       // Drop Shadow
       'dropshadow' => '0 2px 12px rgba(0, 0, 0, .20)',
diff --git a/src/applications/celerity/postprocessor/CelerityDefaultPostprocessor.php b/src/applications/celerity/postprocessor/CelerityDefaultPostprocessor.php
--- a/src/applications/celerity/postprocessor/CelerityDefaultPostprocessor.php
+++ b/src/applications/celerity/postprocessor/CelerityDefaultPostprocessor.php
@@ -20,13 +20,13 @@
   public function buildVariables() {
     return array(
       // Fonts
-      'basefont' => "13px -apple-system, system-ui, BlinkMacSystemFont, ".
-        "'Segoe UI', 'Segoe UI Emoji', 'Segoe UI Symbol', 'Lato', ".
-        "'Helvetica Neue', Helvetica, Arial, sans-serif",
+      'basefont' => "13px 'Segoe UI', 'Segoe UI Emoji', ".
+        "'Segoe UI Symbol', 'Lato', 'Helvetica Neue', ".
+        "Helvetica, Arial, sans-serif",
 
-      'fontfamily' => "-apple-system, system-ui, BlinkMacSystemFont, ".
-        "'Segoe UI', 'Segoe UI Emoji', 'Segoe UI Symbol', 'Lato', ".
-        "'Helvetica Neue', Helvetica, Arial, sans-serif",
+      'fontfamily' => "'Segoe UI', 'Segoe UI Emoji', ".
+        "'Segoe UI Symbol', 'Lato', 'Helvetica Neue', ".
+        "Helvetica, Arial, sans-serif",
 
       // Drop Shadow
       'dropshadow' => '0 2px 12px rgba(0, 0, 0, .20)',
diff --git a/src/applications/celerity/postprocessor/CelerityLargeFontPostprocessor.php b/src/applications/celerity/postprocessor/CelerityLargeFontPostprocessor.php
--- a/src/applications/celerity/postprocessor/CelerityLargeFontPostprocessor.php
+++ b/src/applications/celerity/postprocessor/CelerityLargeFontPostprocessor.php
@@ -14,9 +14,9 @@
   public function buildVariables() {
     return array(
 
-      'basefont' => "14px -apple-system, system-ui, BlinkMacSystemFont, ".
-        "'Segoe UI', 'Segoe UI Web Regular', 'Segoe UI Symbol', 'Lato', ".
-        "'Helvetica Neue', Helvetica, Arial, sans-serif",
+      'basefont' => "14px 'Segoe UI', 'Segoe UI Web Regular', ".
+        "'Segoe UI Symbol', 'Lato', 'Helvetica Neue', Helvetica, ".
+        "Arial, sans-serif",
 
       // Font Sizes
       'biggestfontsize' => '16px',
diff --git a/webroot/rsrc/css/application/config/config-template.css b/webroot/rsrc/css/application/config/config-template.css
--- a/webroot/rsrc/css/application/config/config-template.css
+++ b/webroot/rsrc/css/application/config/config-template.css
@@ -6,8 +6,7 @@
   background: #f9f9f9;
   margin: 0;
   padding: 0;
-  font: 13px/1.231 -apple-system, system-ui, BlinkMacSystemFont,
-    'Segoe UI', 'Segoe UI Web Regular', 'Segoe UI Symbol',
+  font: 13px/1.231 'Segoe UI', 'Segoe UI Web Regular', 'Segoe UI Symbol',
     'Helvetica Neue', Helvetica, Arial, sans-serif;
   text-align: left;
   -webkit-text-size-adjust: none;
diff --git a/webroot/rsrc/css/application/harbormaster/harbormaster.css b/webroot/rsrc/css/application/harbormaster/harbormaster.css
--- a/webroot/rsrc/css/application/harbormaster/harbormaster.css
+++ b/webroot/rsrc/css/application/harbormaster/harbormaster.css
@@ -103,8 +103,7 @@
 
 .harbormaster-log-expand-table td {
   vertical-align: middle;
-  font: 13px -apple-system, system-ui, BlinkMacSystemFont,
-    'Segoe UI', 'Segoe UI Emoji', 'Segoe UI Symbol', 'Lato',
+  font: 13px 'Segoe UI', 'Segoe UI Emoji', 'Segoe UI Symbol', 'Lato',
     'Helvetica Neue', Helvetica, Arial, sans-serif;
 }