--- a/browser/components/search/content/search.xml
+++ b/browser/components/search/content/search.xml
@@ -1197,17 +1197,17 @@
                        class="search-panel-one-offs"
                        xbl:inherits="compact">
         <xul:button anonid="search-settings-compact"
                     oncommand="showSettings();"
                     class="searchbar-engine-one-off-item search-setting-button-compact"
                     tooltiptext="&changeSearchSettings.tooltip;"
                     xbl:inherits="compact"/>
       </xul:description>
-      <xul:vbox anonid="add-engines"/>
+      <xul:vbox anonid="add-engines" class="search-add-engines"/>
       <xul:button anonid="search-settings"
                   oncommand="showSettings();"
                   class="search-setting-button search-panel-header"
                   label="&changeSearchSettings.button;"
                   xbl:inherits="compact"/>
       <xul:menupopup anonid="search-one-offs-context-menu">
         <xul:menuitem anonid="search-one-offs-context-open-in-new-tab"
                       label="&searchInNewTab.label;"

--- a/browser/themes/linux/searchbar.css
+++ b/browser/themes/linux/searchbar.css
@@ -178,16 +178,17 @@ menuitem[cmd="cmd_clearhistory"][disable
 
 .search-panel-input-value {
   color: -moz-fieldtext;
 }
 
 .search-panel-one-offs {
   margin: 0 !important;
   border-top: 1px solid var(--panel-separator-color);
+  background-color: var(--arrowpanel-dimmed);
 }
 
 .searchbar-engine-one-off-item {
   -moz-appearance: none;
   display: inline-block;
   border: none;
   min-width: 48px;
   height: 32px;
@@ -217,17 +218,16 @@ menuitem[cmd="cmd_clearhistory"][disable
 .search-panel-one-offs[compact=true] > .searchbar-engine-one-off-item.last-of-row:not(.dummy),
 .search-panel-one-offs[compact=true] > .searchbar-engine-one-off-item.dummy:not(.last-of-row),
 .search-panel-one-offs[compact=true] > .searchbar-engine-one-off-item.last-engine,
 .search-setting-button-compact {
   background-image: none;
 }
 
 .searchbar-engine-one-off-item:not([selected]):not(.dummy):hover,
-.search-setting-button:hover,
 .addengine-item:hover {
   background-color: hsla(0, 0%, 0%, 0.06);
   color: inherit;
 }
 
 .searchbar-engine-one-off-item[selected] {
   background-color: Highlight;
   background-image: none;
@@ -245,16 +245,20 @@ menuitem[cmd="cmd_clearhistory"][disable
 
 .searchbar-engine-one-off-item > .button-box > .button-icon {
   display: -moz-box;
   margin-inline-end: 0;
   width: 16px;
   height: 16px;
 }
 
+.search-add-engines {
+  background-color: var(--arrowpanel-dimmed);
+}
+
 .addengine-item {
   -moz-appearance: none;
   background-color: transparent;
   color: inherit;
   border: none;
   height: 32px;
   margin: 0;
   padding: 0 10px;
@@ -339,16 +343,17 @@ menuitem[cmd="cmd_clearhistory"][disable
 }
 
 .search-setting-button {
   -moz-appearance: none;
   margin: 0;
   min-height: 32px;
 }
 
+.search-setting-button:hover,
 .search-setting-button[selected] {
   background-color: var(--arrowpanel-dimmed-further);
 }
 
 .search-setting-button-compact > .button-box > .button-icon {
   list-style-image: url("chrome://browser/skin/gear.svg");
   filter: url(chrome://global/skin/filters.svg#fill);
   fill: currentColor;

--- a/browser/themes/osx/searchbar.css
+++ b/browser/themes/osx/searchbar.css
@@ -168,16 +168,17 @@
 
 .search-panel-input-value {
   color: -moz-fieldtext;
 }
 
 .search-panel-one-offs {
   margin: 0 !important;
   border-top: 1px solid var(--panel-separator-color);
+  background-color: var(--arrowpanel-dimmed);
 }
 
 .searchbar-engine-one-off-item {
   -moz-appearance: none;
   display: inline-block;
   min-width: 48px;
   height: 32px;
   margin: 0;
@@ -206,17 +207,16 @@
 .search-panel-one-offs[compact=true] > .searchbar-engine-one-off-item.last-of-row:not(.dummy),
 .search-panel-one-offs[compact=true] > .searchbar-engine-one-off-item.dummy:not(.last-of-row),
 .search-panel-one-offs[compact=true] > .searchbar-engine-one-off-item.last-engine,
 .search-setting-button-compact {
   background-image: none;
 }
 
 .searchbar-engine-one-off-item:not([selected]):not(.dummy):hover,
-.search-setting-button:hover,
 .addengine-item:hover {
   background-color: hsla(0, 0%, 0%, 0.06);
   color: inherit;
 }
 
 .searchbar-engine-one-off-item[selected] {
   background-color: Highlight;
   background-image: none;
@@ -228,16 +228,20 @@
 }
 
 .searchbar-engine-one-off-item > .button-box > .button-icon {
   margin-inline-start: 0;
   width: 16px;
   height: 16px;
 }
 
+.search-add-engines {
+  background-color: var(--arrowpanel-dimmed);
+}
+
 .addengine-item {
   -moz-appearance: none;
   font-size: 10px;
   height: 32px;
   margin: 0;
   padding: 0 10px;
 }
 
@@ -321,16 +325,17 @@
 }
 
 .search-setting-button {
   -moz-appearance: none;
   border-radius: 0 0 4px 4px;
   min-height: 32px;
 }
 
+.search-setting-button:hover,
 .search-setting-button[selected] {
   background-color: var(--arrowpanel-dimmed-further);
 }
 
 .search-setting-button-compact > .button-box > .button-icon {
   list-style-image: url("chrome://browser/skin/gear.svg");
   filter: url(chrome://global/skin/filters.svg#fill);
   fill: currentColor;

--- a/browser/themes/windows/searchbar.css
+++ b/browser/themes/windows/searchbar.css
@@ -175,16 +175,17 @@
 .search-panel-input-value {
   color: -moz-fieldtext;
 }
 
 .search-panel-one-offs {
   margin: 0 !important;
   border-top: 1px solid var(--panel-separator-color);
   line-height: 0;
+  background-color: var(--arrowpanel-dimmed);
 }
 
 .searchbar-engine-one-off-item {
   -moz-appearance: none;
   display: inline-block;
   border: none;
   min-width: 48px;
   height: 32px;
@@ -214,17 +215,16 @@
 .search-panel-one-offs[compact=true] > .searchbar-engine-one-off-item.last-of-row:not(.dummy),
 .search-panel-one-offs[compact=true] > .searchbar-engine-one-off-item.dummy:not(.last-of-row),
 .search-panel-one-offs[compact=true] > .searchbar-engine-one-off-item.last-engine,
 .search-setting-button-compact {
   background-image: none;
 }
 
 .searchbar-engine-one-off-item:not([selected]):not(.dummy):hover,
-.search-setting-button:hover,
 .addengine-item:hover {
   background-color: hsla(0, 0%, 0%, 0.06);
   color: inherit;
 }
 
 .searchbar-engine-one-off-item[selected] {
   background-color: Highlight;
   background-image: none;
@@ -240,16 +240,20 @@
   display: none;
 }
 
 .searchbar-engine-one-off-item > .button-box > .button-icon {
   width: 16px;
   height: 16px;
 }
 
+.search-add-engines {
+  background-color: var(--arrowpanel-dimmed);
+}
+
 .addengine-item {
   -moz-appearance: none;
   border: none;
   height: 32px;
   margin: 0;
   padding: 0 10px;
 }
 
@@ -331,16 +335,17 @@
   list-style-image: url("chrome://browser/skin/search-history-icon.svg#search-history-icon-active");
 }
 
 .search-setting-button {
   -moz-appearance: none;
   min-height: 32px;
 }
 
+.search-setting-button:hover,
 .search-setting-button[selected] {
   background-color: var(--arrowpanel-dimmed-further);
 }
 
 .search-setting-button-compact > .button-box > .button-icon {
   list-style-image: url("chrome://browser/skin/gear.svg");
   filter: url(chrome://global/skin/filters.svg#fill);
   fill: currentColor;