Use double quotes and go_to

Author: route

lib/ferrum/page/frames.rb

@@ -75,7 +75,7 @@ def frames_subscribe
           frame_id = params.dig("context", "auxData", "frameId")
 
           unless @main_frame.id
-            root_frame = command('Page.getFrameTree').dig('frameTree', 'frame', 'id')
+            root_frame = command("Page.getFrameTree").dig("frameTree", "frame", "id")
             if frame_id == root_frame
               @main_frame.id = frame_id
               @frames[frame_id] = @main_frame

spec/frame_spec.rb

@@ -27,9 +27,11 @@ module Ferrum
         expect(frame.url).to end_with("/ferrum/get_cookie")
       end
 
-      it 'finds main frame properly' do
-        browser.goto("/ferrum/popup_frames")
+      it "finds main frame properly" do
+        browser.go_to("/ferrum/popup_frames")
+
         browser.at_xpath("//a[text()='pop up']").click
+
         expect(browser.pages.size).to eq(2)
         opened_page = browser.pages.last
         expect(opened_page.main_frame.url).to end_with("/frames")