diff --git a/changelogs/unreleased/fix-u2f-for-opera.yml b/changelogs/unreleased/fix-u2f-for-opera.yml
new file mode 100644
index 00000000000..0eafb8eff9a
--- /dev/null
+++ b/changelogs/unreleased/fix-u2f-for-opera.yml
@@ -0,0 +1,4 @@
+---
+title: Fix FIDO U2F for Opera browser
+merge_request: 12082
+author: Jakub Kramarz and Jonas Kalderstam
diff --git a/spec/helpers/u2f_helper_spec.rb b/spec/helpers/u2f_helper_spec.rb
new file mode 100644
index 00000000000..0d65b4fe0b8
--- /dev/null
+++ b/spec/helpers/u2f_helper_spec.rb
@@ -0,0 +1,49 @@
+require 'spec_helper'
+
+describe U2fHelper do
+  describe 'when not on mobile' do
+    it 'does not inject u2f on chrome 40' do
+      device = double(mobile?: false)
+      browser = double(chrome?: true, opera?: false, version: 40, device: device)
+      allow(helper).to receive(:browser).and_return(browser)
+      expect(helper.inject_u2f_api?).to eq false
+    end
+
+    it 'injects u2f on chrome 41' do
+      device = double(mobile?: false)
+      browser = double(chrome?: true, opera?: false, version: 41, device: device)
+      allow(helper).to receive(:browser).and_return(browser)
+      expect(helper.inject_u2f_api?).to eq true
+    end
+
+    it 'does not inject u2f on opera 39' do
+      device = double(mobile?: false)
+      browser = double(chrome?: false, opera?: true, version: 39, device: device)
+      allow(helper).to receive(:browser).and_return(browser)
+      expect(helper.inject_u2f_api?).to eq false
+    end
+
+    it 'injects u2f on opera 40' do
+      device = double(mobile?: false)
+      browser = double(chrome?: false, opera?: true, version: 40, device: device)
+      allow(helper).to receive(:browser).and_return(browser)
+      expect(helper.inject_u2f_api?).to eq true
+    end
+  end
+
+  describe 'when on mobile' do
+    it 'does not inject u2f on chrome 41' do
+      device = double(mobile?: true)
+      browser = double(chrome?: true, opera?: false, version: 41, device: device)
+      allow(helper).to receive(:browser).and_return(browser)
+      expect(helper.inject_u2f_api?).to eq false
+    end
+
+    it 'does not inject u2f on opera 40' do
+      device = double(mobile?: true)
+      browser = double(chrome?: false, opera?: true, version: 40, device: device)
+      allow(helper).to receive(:browser).and_return(browser)
+      expect(helper.inject_u2f_api?).to eq false
+    end
+  end
+end