diff --git a/packages/tailwindcss-language-server/tests/env/custom-languages.test.js b/packages/tailwindcss-language-server/tests/env/custom-languages.test.js
index c59e076d..34725c6f 100644
--- a/packages/tailwindcss-language-server/tests/env/custom-languages.test.js
+++ b/packages/tailwindcss-language-server/tests/env/custom-languages.test.js
@@ -1,6 +1,6 @@
 import { test } from 'vitest'
 import { init } from '../common'
-import { HoverRequest } from 'vscode-languageserver'
+import { CompletionRequest, HoverRequest } from 'vscode-languageserver'
 
 test('Unknown languages do not provide completions', async ({ expect }) => {
   let c = await init('basic')
@@ -16,6 +16,14 @@ test('Unknown languages do not provide completions', async ({ expect }) => {
   })
 
   expect(hover).toEqual(null)
+
+  let completion = await c.sendRequest(CompletionRequest.type, {
+    textDocument,
+    position: { line: 0, character: 13 },
+    context: { triggerKind: 1 },
+  })
+
+  expect(completion).toBe(null)
 })
 
 test('Custom languages may be specified via init options (deprecated)', async ({ expect }) => {
@@ -43,6 +51,14 @@ test('Custom languages may be specified via init options (deprecated)', async ({
     },
     range: { start: { line: 0, character: 12 }, end: { line: 0, character: 21 } },
   })
+
+  let completion = await c.sendRequest(CompletionRequest.type, {
+    textDocument,
+    position: { line: 0, character: 13 },
+    context: { triggerKind: 1 },
+  })
+
+  expect(completion.items.length).toBe(11509)
 })
 
 test('Custom languages may be specified via settings', async ({ expect }) => {
@@ -74,6 +90,14 @@ test('Custom languages may be specified via settings', async ({ expect }) => {
     },
     range: { start: { line: 0, character: 12 }, end: { line: 0, character: 21 } },
   })
+
+  let completion = await c.sendRequest(CompletionRequest.type, {
+    textDocument,
+    position: { line: 0, character: 13 },
+    context: { triggerKind: 1 },
+  })
+
+  expect(completion.items.length).toBe(11509)
 })
 
 test('Custom languages are merged from init options and settings', async ({ expect }) => {
@@ -101,6 +125,12 @@ test('Custom languages are merged from init options and settings', async ({ expe
     position: { line: 0, character: 13 },
   })
 
+  let completion = await c.sendRequest(CompletionRequest.type, {
+    textDocument,
+    position: { line: 0, character: 13 },
+    context: { triggerKind: 1 },
+  })
+
   textDocument = await c.openDocument({
     lang: 'other-lang',
     text: '<div class="bg-[#000]">',
@@ -111,6 +141,12 @@ test('Custom languages are merged from init options and settings', async ({ expe
     position: { line: 0, character: 13 },
   })
 
+  let completion2 = await c.sendRequest(CompletionRequest.type, {
+    textDocument,
+    position: { line: 0, character: 13 },
+    context: { triggerKind: 1 },
+  })
+
   expect(hover).toEqual({
     contents: {
       language: 'css',
@@ -128,6 +164,9 @@ test('Custom languages are merged from init options and settings', async ({ expe
     },
     range: { start: { line: 0, character: 12 }, end: { line: 0, character: 21 } },
   })
+
+  expect(completion.items.length).toBe(11509)
+  expect(completion2.items.length).toBe(11509)
 })
 
 test('Language mappings from settings take precedence', async ({ expect }) => {
@@ -163,4 +202,12 @@ test('Language mappings from settings take precedence', async ({ expect }) => {
     },
     range: { start: { line: 0, character: 12 }, end: { line: 0, character: 21 } },
   })
+
+  let completion = await c.sendRequest(CompletionRequest.type, {
+    textDocument,
+    position: { line: 0, character: 13 },
+    context: { triggerKind: 1 },
+  })
+
+  expect(completion.items.length).toBe(11509)
 })