diff --git a/rb/lib/selenium/webdriver/firefox/extension.rb b/rb/lib/selenium/webdriver/firefox/extension.rb
index 1f268d6021e76..674eac2acd8c7 100644
--- a/rb/lib/selenium/webdriver/firefox/extension.rb
+++ b/rb/lib/selenium/webdriver/firefox/extension.rb
@@ -87,6 +87,14 @@ def read_id_from_manifest_json(directory)
           return unless File.exist?(manifest_path)
 
           manifest = JSON.parse(File.read(manifest_path))
+          applications_gecko_id(manifest) || name_and_version(manifest)
+        end
+
+        def applications_gecko_id(manifest)
+          manifest.dig('applications', 'gecko', 'id')&.strip
+        end
+
+        def name_and_version(manifest)
           [manifest['name'].delete(' '), manifest['version']].join('@')
         end
       end # Extension
diff --git a/rb/spec/integration/selenium/webdriver/firefox/profile_spec.rb b/rb/spec/integration/selenium/webdriver/firefox/profile_spec.rb
index bc3ce1e6bedeb..38f76c67501e9 100644
--- a/rb/spec/integration/selenium/webdriver/firefox/profile_spec.rb
+++ b/rb/spec/integration/selenium/webdriver/firefox/profile_spec.rb
@@ -147,13 +147,20 @@ def read_generated_prefs(from = nil)
           expect(Dir.exist?(extension_directory)).to eq(true)
         end
 
-        it 'can install web extension' do
+        it 'can install web extension without id' do
           mooltipass = File.expand_path('../../../../../../third_party/firebug/mooltipass-1.1.87.xpi', __dir__)
           profile.add_extension(mooltipass)
           extension_directory = File.expand_path('extensions/MooltipassExtension@1.1.87', profile.layout_on_disk)
           expect(Dir.exist?(extension_directory)).to eq(true)
         end
 
+        it 'can install web extension with id' do
+          ext = File.expand_path('../../../../../../third_party/firebug/favourite_colour-1.1-an+fx.xpi', __dir__)
+          profile.add_extension(ext)
+          extension_directory = File.expand_path('extensions/favourite-colour-examples@mozilla.org', profile.layout_on_disk)
+          expect(Dir.exist?(extension_directory)).to eq(true)
+        end
+
         describe 'with browser' do
           before do
             profile['browser.startup.homepage'] = url_for('simpleTest.html')
diff --git a/third_party/firebug/favourite_colour-1.1-an+fx.xpi b/third_party/firebug/favourite_colour-1.1-an+fx.xpi
new file mode 100644
index 0000000000000..1982a588bc025
Binary files /dev/null and b/third_party/firebug/favourite_colour-1.1-an+fx.xpi differ