diff --git a/src/vs/workbench/contrib/styleOverrides/browser/media/activityBar.css b/src/vs/workbench/contrib/styleOverrides/browser/media/activityBar.css
index f804fffd519..96dd75ab461 100644
--- a/src/vs/workbench/contrib/styleOverrides/browser/media/activityBar.css
+++ b/src/vs/workbench/contrib/styleOverrides/browser/media/activityBar.css
@@ -341,16 +341,40 @@
 	overflow: visible;
 }
 
+/* When badge-content is empty (icon-only via ::before, e.g. the update badge), use uniform padding so it stays circular. */
+.style-override.monaco-workbench .pane-composite-part > .title > .composite-bar-container > .composite-bar > .monaco-action-bar .badge .badge-content:empty,
+.style-override.monaco-workbench .pane-composite-part > .header-or-footer > .composite-bar-container > .composite-bar > .monaco-action-bar .badge .badge-content:empty {
+	padding: 2px;
+}
+
+.style-override.monaco-workbench .pane-composite-part > .title > .composite-bar-container > .composite-bar > .monaco-action-bar .action-item.icon .badge.compact .badge-content:empty,
+.style-override.monaco-workbench .pane-composite-part > .header-or-footer > .composite-bar-container > .composite-bar > .monaco-action-bar .action-item.icon .badge.compact .badge-content:empty {
+	padding: 0;
+	border-radius: var(--vscode-cornerRadius-circle);
+}
+
 .style-override.monaco-workbench .activitybar > .content :not(.monaco-menu) > .monaco-action-bar .badge .badge-content {
 	top: 18px;
 	right: 2px;
 }
 
+.style-override.monaco-workbench .activitybar > .content :not(.monaco-menu) > .monaco-action-bar .badge .badge-content:empty {
+	padding: 0;
+	border-radius: var(--vscode-cornerRadius-circle);
+	width: 16px;
+}
+
 .style-override.monaco-workbench .activitybar.compact > .content :not(.monaco-menu) > .monaco-action-bar .badge .badge-content {
 	top: 13px;
 	right: 2px;
 }
 
+.style-override.monaco-workbench .activitybar.compact > .content :not(.monaco-menu) > .monaco-action-bar .badge .badge-content:empty {
+	padding: 0;
+	border-radius: var(--vscode-cornerRadius-circle);
+	width: 13px;
+}
+
 .style-override.monaco-workbench .pane-composite-part > .header-or-footer > .composite-bar-container > .composite-bar > .monaco-action-bar .action-item:focus .active-item-indicator {
 	overflow: visible;
 }