diff --git a/platform/commonUI/general/res/sass/_constants.scss b/platform/commonUI/general/res/sass/_constants.scss
index a3305cf0a4..e0d9f34bd6 100644
--- a/platform/commonUI/general/res/sass/_constants.scss
+++ b/platform/commonUI/general/res/sass/_constants.scss
@@ -44,9 +44,10 @@ $ueAppLogoW: 105px;
 $ueEditToolBarH: 25px;
 $ueBrowseLeftPaneTreeW: 25%;
 $ueBrowseRightPaneInspectW: 20%;
-$ueCollapsedPaneEdgeM: 20px;
+$ueCollapsedPaneEdgeM: 22px;
 $uePaneMiniTabH: $ueTopBarH;
 $uePaneMiniTabW: 9px;
+$uePaneMiniTabCollapsedW: 11px;
 $ueEditLeftPaneW: 75%;
 $treeSearchInputBarH: 25px;
 $ueTimeControlH: (33px, 20px, 20px);
diff --git a/platform/commonUI/general/res/sass/controls/_buttons.scss b/platform/commonUI/general/res/sass/controls/_buttons.scss
index 956e144899..5431b0f563 100644
--- a/platform/commonUI/general/res/sass/controls/_buttons.scss
+++ b/platform/commonUI/general/res/sass/controls/_buttons.scss
@@ -225,6 +225,11 @@ $pad: $interiorMargin * $baseRatio;
         overflow: hidden;
         word-break: break-all;
 
+        &.collapsed {
+            $d: $uePaneMiniTabCollapsedW;
+            width: $d; font-size: $d;
+        }
+
         &:before,
         &:after {
             position: absolute;
diff --git a/platform/commonUI/themes/espresso/res/css/theme-espresso.css b/platform/commonUI/themes/espresso/res/css/theme-espresso.css
index 6cffc059da..d0d1a2c63b 100644
--- a/platform/commonUI/themes/espresso/res/css/theme-espresso.css
+++ b/platform/commonUI/themes/espresso/res/css/theme-espresso.css
@@ -507,35 +507,35 @@ mct-container {
     padding: 5px 0; }
 
 /********************************************* FLEX STYLES */
-/* line 95, ../../../../general/res/sass/_archetypes.scss */
+/* line 96, ../../../../general/res/sass/_archetypes.scss */
 .l-flex-row, .l-flex,
 .l-flex-col {
   display: -webkit-flex;
   display: flex;
   -webkit-flex-wrap: nowrap;
   flex-wrap: nowrap; }
-  /* line 100, ../../../../general/res/sass/_archetypes.scss */
+  /* line 101, ../../../../general/res/sass/_archetypes.scss */
   .l-flex-row .flex-elem:not(.grows), .l-flex .flex-elem:not(.grows),
   .l-flex-col .flex-elem:not(.grows) {
     -webkit-flex: 0 1 auto;
     flex: 0 1 auto; }
-  /* line 103, ../../../../general/res/sass/_archetypes.scss */
+  /* line 104, ../../../../general/res/sass/_archetypes.scss */
   .l-flex-row .flex-elem.grows, .l-flex .flex-elem.grows,
   .l-flex-col .flex-elem.grows {
     -webkit-flex: 1 1 auto;
     flex: 1 1 auto; }
 
-/* line 109, ../../../../general/res/sass/_archetypes.scss */
+/* line 110, ../../../../general/res/sass/_archetypes.scss */
 .l-flex-row, .l-flex {
   -webkit-flex-direction: row;
   flex-direction: row; }
 
-/* line 110, ../../../../general/res/sass/_archetypes.scss */
+/* line 111, ../../../../general/res/sass/_archetypes.scss */
 .l-flex-col {
   -webkit-flex-direction: column;
   flex-direction: column; }
 
-/* line 116, ../../../../general/res/sass/_archetypes.scss */
+/* line 115, ../../../../general/res/sass/_archetypes.scss */
 .l-flex .left {
   -webkit-flex: 1 1 0;
   flex: 1 1 0;
@@ -1895,26 +1895,30 @@ tr[class*="s-limit"].s-limit-lwr td:first-child:before {
     overflow: hidden;
     word-break: break-all; }
     /* line 228, ../../../../general/res/sass/controls/_buttons.scss */
+    .mini-tab-icon.collapsed {
+      width: 11px;
+      font-size: 11px; }
+    /* line 233, ../../../../general/res/sass/controls/_buttons.scss */
     .mini-tab-icon:before, .mini-tab-icon:after {
       position: absolute;
       display: inherit; }
-    /* line 234, ../../../../general/res/sass/controls/_buttons.scss */
+    /* line 239, ../../../../general/res/sass/controls/_buttons.scss */
     .mini-tab-icon:before {
       content: '\78'; }
-    /* line 238, ../../../../general/res/sass/controls/_buttons.scss */
+    /* line 243, ../../../../general/res/sass/controls/_buttons.scss */
     .mini-tab-icon:hover {
       color: #0099cc; } }
 
-/* line 245, ../../../../general/res/sass/controls/_buttons.scss */
+/* line 250, ../../../../general/res/sass/controls/_buttons.scss */
 .l-btn-set {
   font-size: 0; }
-  /* line 251, ../../../../general/res/sass/controls/_buttons.scss */
+  /* line 256, ../../../../general/res/sass/controls/_buttons.scss */
   .l-btn-set .s-btn, .l-btn-set .s-menu-btn {
     -moz-border-radius: 0;
     -webkit-border-radius: 0;
     border-radius: 0;
     margin-left: 1px; }
-  /* line 257, ../../../../general/res/sass/controls/_buttons.scss */
+  /* line 262, ../../../../general/res/sass/controls/_buttons.scss */
   .l-btn-set .first .s-btn, .l-btn-set .first .s-menu-btn {
     -moz-border-radius-topleft: 3px;
     -webkit-border-top-left-radius: 3px;
@@ -1923,7 +1927,7 @@ tr[class*="s-limit"].s-limit-lwr td:first-child:before {
     -webkit-border-bottom-left-radius: 3px;
     border-bottom-left-radius: 3px;
     margin-left: 0; }
-  /* line 264, ../../../../general/res/sass/controls/_buttons.scss */
+  /* line 269, ../../../../general/res/sass/controls/_buttons.scss */
   .l-btn-set .last .s-btn, .l-btn-set .last .s-menu-btn {
     -moz-border-radius-topright: 3px;
     -webkit-border-top-right-radius: 3px;
@@ -1932,7 +1936,7 @@ tr[class*="s-limit"].s-limit-lwr td:first-child:before {
     -webkit-border-bottom-right-radius: 3px;
     border-bottom-right-radius: 3px; }
 
-/* line 271, ../../../../general/res/sass/controls/_buttons.scss */
+/* line 276, ../../../../general/res/sass/controls/_buttons.scss */
 .paused:not(.s-btn):not(.s-menu-btn) {
   border-color: #c56f01 !important;
   color: #c56f01 !important; }
@@ -4533,10 +4537,10 @@ span.req {
           /* line 240, ../../../../general/res/sass/user-environ/_layout.scss */
           .pane .mini-tab-icon.toggle-pane.toggle-tree.anchor-left.collapsed {
             left: 0;
-            -moz-transform: translateX(-15px);
-            -ms-transform: translateX(-15px);
-            -webkit-transform: translateX(-15px);
-            transform: translateX(-15px); }
+            -moz-transform: translateX(-17px);
+            -ms-transform: translateX(-17px);
+            -webkit-transform: translateX(-17px);
+            transform: translateX(-17px); }
           /* line 244, ../../../../general/res/sass/user-environ/_layout.scss */
           .pane .mini-tab-icon.toggle-pane.toggle-tree.anchor-left:not(.collapsed):before {
             -moz-transition-property: opacity;
@@ -4757,11 +4761,11 @@ span.req {
 
   /* line 418, ../../../../general/res/sass/user-environ/_layout.scss */
   .pane-tree-hidden .pane.right.primary-pane {
-    left: 20px !important; }
+    left: 22px !important; }
 
   /* line 421, ../../../../general/res/sass/user-environ/_layout.scss */
   .pane-inspect-hidden .l-object-and-inspector .pane.left {
-    right: 20px !important; }
+    right: 22px !important; }
 
   /* line 424, ../../../../general/res/sass/user-environ/_layout.scss */
   .pane:not(.resizing) {
diff --git a/platform/commonUI/themes/snow/res/css/theme-snow.css b/platform/commonUI/themes/snow/res/css/theme-snow.css
index cc80ecd0df..1e3717427f 100644
--- a/platform/commonUI/themes/snow/res/css/theme-snow.css
+++ b/platform/commonUI/themes/snow/res/css/theme-snow.css
@@ -507,35 +507,35 @@ mct-container {
     padding: 5px 0; }
 
 /********************************************* FLEX STYLES */
-/* line 95, ../../../../general/res/sass/_archetypes.scss */
+/* line 96, ../../../../general/res/sass/_archetypes.scss */
 .l-flex-row, .l-flex,
 .l-flex-col {
   display: -webkit-flex;
   display: flex;
   -webkit-flex-wrap: nowrap;
   flex-wrap: nowrap; }
-  /* line 100, ../../../../general/res/sass/_archetypes.scss */
+  /* line 101, ../../../../general/res/sass/_archetypes.scss */
   .l-flex-row .flex-elem:not(.grows), .l-flex .flex-elem:not(.grows),
   .l-flex-col .flex-elem:not(.grows) {
     -webkit-flex: 0 1 auto;
     flex: 0 1 auto; }
-  /* line 103, ../../../../general/res/sass/_archetypes.scss */
+  /* line 104, ../../../../general/res/sass/_archetypes.scss */
   .l-flex-row .flex-elem.grows, .l-flex .flex-elem.grows,
   .l-flex-col .flex-elem.grows {
     -webkit-flex: 1 1 auto;
     flex: 1 1 auto; }
 
-/* line 109, ../../../../general/res/sass/_archetypes.scss */
+/* line 110, ../../../../general/res/sass/_archetypes.scss */
 .l-flex-row, .l-flex {
   -webkit-flex-direction: row;
   flex-direction: row; }
 
-/* line 110, ../../../../general/res/sass/_archetypes.scss */
+/* line 111, ../../../../general/res/sass/_archetypes.scss */
 .l-flex-col {
   -webkit-flex-direction: column;
   flex-direction: column; }
 
-/* line 116, ../../../../general/res/sass/_archetypes.scss */
+/* line 115, ../../../../general/res/sass/_archetypes.scss */
 .l-flex .left {
   -webkit-flex: 1 1 0;
   flex: 1 1 0;
@@ -1840,26 +1840,30 @@ tr[class*="s-limit"].s-limit-lwr td:first-child:before {
     overflow: hidden;
     word-break: break-all; }
     /* line 228, ../../../../general/res/sass/controls/_buttons.scss */
+    .mini-tab-icon.collapsed {
+      width: 11px;
+      font-size: 11px; }
+    /* line 233, ../../../../general/res/sass/controls/_buttons.scss */
     .mini-tab-icon:before, .mini-tab-icon:after {
       position: absolute;
       display: inherit; }
-    /* line 234, ../../../../general/res/sass/controls/_buttons.scss */
+    /* line 239, ../../../../general/res/sass/controls/_buttons.scss */
     .mini-tab-icon:before {
       content: '\78'; }
-    /* line 238, ../../../../general/res/sass/controls/_buttons.scss */
+    /* line 243, ../../../../general/res/sass/controls/_buttons.scss */
     .mini-tab-icon:hover {
       color: #0099cc; } }
 
-/* line 245, ../../../../general/res/sass/controls/_buttons.scss */
+/* line 250, ../../../../general/res/sass/controls/_buttons.scss */
 .l-btn-set {
   font-size: 0; }
-  /* line 251, ../../../../general/res/sass/controls/_buttons.scss */
+  /* line 256, ../../../../general/res/sass/controls/_buttons.scss */
   .l-btn-set .s-btn, .l-btn-set .s-menu-btn {
     -moz-border-radius: 0;
     -webkit-border-radius: 0;
     border-radius: 0;
     margin-left: 1px; }
-  /* line 257, ../../../../general/res/sass/controls/_buttons.scss */
+  /* line 262, ../../../../general/res/sass/controls/_buttons.scss */
   .l-btn-set .first .s-btn, .l-btn-set .first .s-menu-btn {
     -moz-border-radius-topleft: 4px;
     -webkit-border-top-left-radius: 4px;
@@ -1868,7 +1872,7 @@ tr[class*="s-limit"].s-limit-lwr td:first-child:before {
     -webkit-border-bottom-left-radius: 4px;
     border-bottom-left-radius: 4px;
     margin-left: 0; }
-  /* line 264, ../../../../general/res/sass/controls/_buttons.scss */
+  /* line 269, ../../../../general/res/sass/controls/_buttons.scss */
   .l-btn-set .last .s-btn, .l-btn-set .last .s-menu-btn {
     -moz-border-radius-topright: 4px;
     -webkit-border-top-right-radius: 4px;
@@ -1877,7 +1881,7 @@ tr[class*="s-limit"].s-limit-lwr td:first-child:before {
     -webkit-border-bottom-right-radius: 4px;
     border-bottom-right-radius: 4px; }
 
-/* line 271, ../../../../general/res/sass/controls/_buttons.scss */
+/* line 276, ../../../../general/res/sass/controls/_buttons.scss */
 .paused:not(.s-btn):not(.s-menu-btn) {
   border-color: #ff9900 !important;
   color: #ff9900 !important; }
@@ -4455,10 +4459,10 @@ span.req {
           /* line 240, ../../../../general/res/sass/user-environ/_layout.scss */
           .pane .mini-tab-icon.toggle-pane.toggle-tree.anchor-left.collapsed {
             left: 0;
-            -moz-transform: translateX(-15px);
-            -ms-transform: translateX(-15px);
-            -webkit-transform: translateX(-15px);
-            transform: translateX(-15px); }
+            -moz-transform: translateX(-17px);
+            -ms-transform: translateX(-17px);
+            -webkit-transform: translateX(-17px);
+            transform: translateX(-17px); }
           /* line 244, ../../../../general/res/sass/user-environ/_layout.scss */
           .pane .mini-tab-icon.toggle-pane.toggle-tree.anchor-left:not(.collapsed):before {
             -moz-transition-property: opacity;
@@ -4679,11 +4683,11 @@ span.req {
 
   /* line 418, ../../../../general/res/sass/user-environ/_layout.scss */
   .pane-tree-hidden .pane.right.primary-pane {
-    left: 20px !important; }
+    left: 22px !important; }
 
   /* line 421, ../../../../general/res/sass/user-environ/_layout.scss */
   .pane-inspect-hidden .l-object-and-inspector .pane.left {
-    right: 20px !important; }
+    right: 22px !important; }
 
   /* line 424, ../../../../general/res/sass/user-environ/_layout.scss */
   .pane:not(.resizing) {