diff --git a/src/renderer/src/AppSidebarLayout.test.ts b/src/renderer/src/AppSidebarLayout.test.ts
new file mode 100644
index 00000000..72949c6b
--- /dev/null
+++ b/src/renderer/src/AppSidebarLayout.test.ts
@@ -0,0 +1,20 @@
+import { readFileSync } from 'node:fs'
+import { join } from 'node:path'
+import { describe, expect, it } from 'vitest'
+
+const stylesheet = readFileSync(
+  join(process.cwd(), 'src', 'renderer', 'src', 'styles.css'),
+  'utf8'
+).replaceAll('\r\n', '\n')
+
+describe('primary sidebar layout', () => {
+  it('keeps the resize hit target from adding space beside the divider', () => {
+    const rule = stylesheet.match(
+      /\.primary-sidebar-resize-handle\s*\{([^}]*)\}/u
+    )?.[1]
+
+    expect(rule).toContain('width: 9px;')
+    expect(rule).toContain('margin-left: -5px;')
+    expect(rule).toContain('margin-right: -4px;')
+  })
+})
diff --git a/src/renderer/src/styles.css b/src/renderer/src/styles.css
index f32db4ad..994abf03 100644
--- a/src/renderer/src/styles.css
+++ b/src/renderer/src/styles.css
@@ -2404,6 +2404,7 @@ textarea:focus-visible {
   min-width: 9px;
   padding: 0;
   margin-left: -5px;
+  margin-right: -4px;
   background: transparent;
   cursor: col-resize;
   touch-action: none;