diff --git a/cinnamon-shell/upstream/cinnamon-dark.css b/cinnamon-shell/upstream/cinnamon-dark.css
index a267a0733e..7d083d8ed0 100644
--- a/cinnamon-shell/upstream/cinnamon-dark.css
+++ b/cinnamon-shell/upstream/cinnamon-dark.css
@@ -1008,6 +1008,58 @@ StScrollBar {
     box-shadow: none;
     background: none; }
 
+.polkit-dialog {
+  width: 500px; }
+  .polkit-dialog-main-layout {
+    spacing: 10px; }
+  .polkit-dialog-headline {
+    color: rgba(255, 255, 255, 0.87);
+    text-align: center;
+    font-size: 1.3em;
+    font-weight: bold; }
+  .polkit-dialog-description {
+    color: rgba(255, 255, 255, 0.87);
+    text-align: center;
+    font-size: 1em; }
+  .polkit-dialog-user-layout {
+    spacing: 10px; }
+  .polkit-dialog-user-layout:rtl {
+    padding-right: 10px; }
+  .polkit-dialog-user-root-label {
+    color: #FC4138; }
+  .polkit-dialog-password-label:ltr {
+    padding-top: 0.5em;
+    padding-right: 0.5em; }
+  .polkit-dialog-password-label:rtl {
+    padding-left: 0.5em; }
+  .polkit-dialog-password-entry {
+    width: 21em;
+    height: 1.2em;
+    padding: 7px;
+    border-radius: 3px;
+    caret-color: #c3c3c3;
+    selected-color: #ffffff;
+    selection-background-color: #35a854;
+    color: #c3c3c3;
+    background-color: rgba(109, 109, 109, 0.4);
+    border: 1px solid rgba(22, 22, 22, 0.4);
+    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.05); }
+    .polkit-dialog-password-entry:focus {
+      color: rgba(255, 255, 255, 0.87);
+      background-color: #404040;
+      border: 1px solid #35a854;
+      box-shadow: inset 0 2px 4px rgba(64, 64, 64, 0.05); }
+    .polkit-dialog-password-entry .caplocks-warning {
+      icon-size: 16px;
+      warning-color: #F27835;
+      padding: 0 4px; }
+  .polkit-dialog-error-label {
+    color: #FC4138;
+    text-align: center;
+    font-size: 1em; }
+  .polkit-dialog-info-label {
+    font-size: 1em; }
+
 /* CinnamonMountOperation Dialogs */
 .cinnamon-mount-operation-icon {
   icon-size: 48px; }
@@ -1640,11 +1692,8 @@ StScrollBar {
     text-shadow: none; }
 
 .user-icon {
-  width: 32px;
-  height: 32px;
-  background-color: transparent;
-  border: none;
-  border-radius: 0; }
+  border: 1px solid rgba(255, 255, 255, 0.37);
+  border-radius: 99px; }
 
 .user-label {
   color: rgba(255, 255, 255, 0.87);
diff --git a/cinnamon-shell/upstream/cinnamon.css b/cinnamon-shell/upstream/cinnamon.css
index 1c5b372a90..5a03436386 100644
--- a/cinnamon-shell/upstream/cinnamon.css
+++ b/cinnamon-shell/upstream/cinnamon.css
@@ -1008,6 +1008,58 @@ StScrollBar {
     box-shadow: none;
     background: none; }
 
+.polkit-dialog {
+  width: 500px; }
+  .polkit-dialog-main-layout {
+    spacing: 10px; }
+  .polkit-dialog-headline {
+    color: #303030;
+    text-align: center;
+    font-size: 1.3em;
+    font-weight: bold; }
+  .polkit-dialog-description {
+    color: #303030;
+    text-align: center;
+    font-size: 1em; }
+  .polkit-dialog-user-layout {
+    spacing: 10px; }
+  .polkit-dialog-user-layout:rtl {
+    padding-right: 10px; }
+  .polkit-dialog-user-root-label {
+    color: #FC4138; }
+  .polkit-dialog-password-label:ltr {
+    padding-top: 0.5em;
+    padding-right: 0.5em; }
+  .polkit-dialog-password-label:rtl {
+    padding-left: 0.5em; }
+  .polkit-dialog-password-entry {
+    width: 21em;
+    height: 1.2em;
+    padding: 7px;
+    border-radius: 3px;
+    caret-color: #c3c3c3;
+    selected-color: #ffffff;
+    selection-background-color: #35a854;
+    color: #c3c3c3;
+    background-color: rgba(109, 109, 109, 0.4);
+    border: 1px solid rgba(22, 22, 22, 0.4);
+    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.05); }
+    .polkit-dialog-password-entry:focus {
+      color: #303030;
+      background-color: #f4f4f4;
+      border: 1px solid #35a854;
+      box-shadow: inset 0 2px 4px rgba(244, 244, 244, 0.05); }
+    .polkit-dialog-password-entry .caplocks-warning {
+      icon-size: 16px;
+      warning-color: #F27835;
+      padding: 0 4px; }
+  .polkit-dialog-error-label {
+    color: #FC4138;
+    text-align: center;
+    font-size: 1em; }
+  .polkit-dialog-info-label {
+    font-size: 1em; }
+
 /* CinnamonMountOperation Dialogs */
 .cinnamon-mount-operation-icon {
   icon-size: 48px; }
@@ -1640,11 +1692,8 @@ StScrollBar {
     text-shadow: none; }
 
 .user-icon {
-  width: 32px;
-  height: 32px;
-  background-color: transparent;
-  border: none;
-  border-radius: 0; }
+  border: 1px solid rgba(48, 48, 48, 0.5);
+  border-radius: 99px; }
 
 .user-label {
   color: #303030;
diff --git a/cinnamon-shell/upstream/mint-y-dark-thumbnail.png b/cinnamon-shell/upstream/mint-y-dark-thumbnail.png
index cf25ac4979..4a5756024f 100644
Binary files a/cinnamon-shell/upstream/mint-y-dark-thumbnail.png and b/cinnamon-shell/upstream/mint-y-dark-thumbnail.png differ
diff --git a/cinnamon-shell/upstream/mint-y-thumbnail.png b/cinnamon-shell/upstream/mint-y-thumbnail.png
index 208cd2c126..cf2c02d38d 100644
Binary files a/cinnamon-shell/upstream/mint-y-thumbnail.png and b/cinnamon-shell/upstream/mint-y-thumbnail.png differ
diff --git a/cinnamon-shell/upstream/parse-sass.sh b/cinnamon-shell/upstream/parse-sass.sh
index b4483da1e8..95e64e7513 100755
--- a/cinnamon-shell/upstream/parse-sass.sh
+++ b/cinnamon-shell/upstream/parse-sass.sh
@@ -1,4 +1,4 @@
 #! /bin/bash
 
-sassc ./sass/cinnamon.scss cinnamon.css
-sassc ./sass/cinnamon-dark.scss cinnamon-dark.css
\ No newline at end of file
+pysassc ./sass/cinnamon.scss cinnamon.css
+pysassc ./sass/cinnamon-dark.scss cinnamon-dark.css
diff --git a/cinnamon-shell/upstream/sass/_common.scss b/cinnamon-shell/upstream/sass/_common.scss
index b93ca417fe..c5e9645fd8 100644
--- a/cinnamon-shell/upstream/sass/_common.scss
+++ b/cinnamon-shell/upstream/sass/_common.scss
@@ -1293,6 +1293,70 @@ StScrollBar {
   }
 }
 
+//
+// Polkit Dialog
+//
+.polkit-dialog {
+  width: 500px;
+
+  &-main-layout { spacing: 10px; }
+
+  &-headline {
+    color: $fg_color;
+    text-align: center;
+    font-size: 1.3em;
+    font-weight: bold;
+  }
+
+  &-description {
+    color: $fg_color;
+    text-align: center;
+    font-size: 1em;
+  }
+
+  &-user-layout { spacing: 10px; }
+  &-user-layout:rtl { padding-right: 10px; }
+
+  &-user-root-label { color: $error_color; }
+
+  &-password-label:ltr {
+    padding-top: 0.5em;
+    padding-right: 0.5em;
+  }
+
+  &-password-label:rtl {
+    padding-left: 0.5em;
+  }
+
+  &-password-entry {
+    width: 21em;
+    height: 1.2em;
+    padding: 7px;
+    border-radius: 3px;
+    caret-color: $osd_fg_color;
+    selected-color: $selected_fg_color;
+    selection-background-color: $selected_bg_color;
+
+    @include entry(osd);
+
+    &:focus { @include entry(focus); }
+
+    .caplocks-warning {
+      icon-size: 16px;
+      warning-color: $warning_color;
+      padding: 0 4px;
+    }
+  }
+
+  &-error-label {
+    color: $error_color;
+    text-align: center;
+    font-size: 1em;
+  }
+
+  &-info-label { font-size: 1em; }
+}
+
 /* CinnamonMountOperation Dialogs */
 .cinnamon-mount-operation-icon {
   icon-size: 48px;
@@ -2136,11 +2200,8 @@ StScrollBar {
 // User Applet
 //
 .user-icon {
-    width: 32px;
-    height: 32px;
-    background-color: transparent;
-    border: none;
-    border-radius: 0;
+    border: 1px solid transparentize($fg_color, 0.5);
+    border-radius: 99px;
 }
 
 .user-label {