diff --git a/spec/spoilers.js b/spec/spoilers.js
index 4914205f7..f32c5772d 100644
--- a/spec/spoilers.js
+++ b/spec/spoilers.js
@@ -153,15 +153,15 @@ describe("A spoiler message", function () {
         await u.waitUntil(() => message_content.textContent === spoiler);
 
         const spoiler_msg_el = view.el.querySelector('.chat-msg__text.spoiler');
-        expect(Array.from(spoiler_msg_el.classList).includes('collapsed')).toBeTruthy();
+        expect(Array.from(spoiler_msg_el.classList).includes('hidden')).toBeTruthy();
 
         spoiler_toggle = view.el.querySelector('.spoiler-toggle');
         expect(spoiler_toggle.textContent.trim()).toBe('Show more');
         spoiler_toggle.click();
-        await u.waitUntil(() => !Array.from(spoiler_msg_el.classList).includes('collapsed'));
+        await u.waitUntil(() => !Array.from(spoiler_msg_el.classList).includes('hidden'));
         expect(spoiler_toggle.textContent.trim()).toBe('Show less');
         spoiler_toggle.click();
-        await u.waitUntil(() => Array.from(spoiler_msg_el.classList).includes('collapsed'));
+        await u.waitUntil(() => Array.from(spoiler_msg_el.classList).includes('hidden'));
         done();
     }));
 
@@ -235,15 +235,15 @@ describe("A spoiler message", function () {
         await u.waitUntil(() => message_content.textContent === spoiler);
 
         const spoiler_msg_el = view.el.querySelector('.chat-msg__text.spoiler');
-        expect(Array.from(spoiler_msg_el.classList).includes('collapsed')).toBeTruthy();
+        expect(Array.from(spoiler_msg_el.classList).includes('hidden')).toBeTruthy();
 
         spoiler_toggle = view.el.querySelector('.spoiler-toggle');
         expect(spoiler_toggle.textContent.trim()).toBe('Show more');
         spoiler_toggle.click();
-        await u.waitUntil(() => !Array.from(spoiler_msg_el.classList).includes('collapsed'));
+        await u.waitUntil(() => !Array.from(spoiler_msg_el.classList).includes('hidden'));
         expect(spoiler_toggle.textContent.trim()).toBe('Show less');
         spoiler_toggle.click();
-        await u.waitUntil(() => Array.from(spoiler_msg_el.classList).includes('collapsed'));
+        await u.waitUntil(() => Array.from(spoiler_msg_el.classList).includes('hidden'));
         done();
     }));
 });
diff --git a/src/components/message.js b/src/components/message.js
index 189ef0d0d..fdbef4301 100644
--- a/src/components/message.js
+++ b/src/components/message.js
@@ -223,7 +223,7 @@ export default class Message extends CustomElement {
                 </a>
             </div>
         `;
-        const spoiler_classes = this.is_spoiler ? `spoiler ${this.is_spoiler_visible ? '' : 'collapsed'}` : '';
+        const spoiler_classes = this.is_spoiler ? `spoiler ${this.is_spoiler_visible ? '' : 'hidden'}` : '';
         return html`
             ${ this.is_spoiler ? tpl_spoiler_hint : '' }
             ${ this.subject ? html`<div class="chat-msg__subject">${this.subject}</div>` : '' }