I am having the same issue. Checked for Opera updates and one was available, updated to 53.0.2907.106 but issue persists. OS is Windows 10 v1803. The site works correctly in Edge browser. Issue persists whether or not logged in to Google, and signed in as different users on Windows.
Further, in the reviews section of an app's information page the summary (5 ratings bars) is displayed but the review texts aren't visible, only a continuously rotating "loading" circle.
Dear Opera creators, a new browser based on Chromium 68 called "Kiwi Browser Android" has just been created.
Browser has some important elements that are missing in Opera:
by default, it also blocks notifications from websites, tracking scripts and automatically agrees to cookies (saving the user from having to click on messages manually);
"Kiwi Browser" also lets you play music and movies in the background. All you need to do is run any recording on YouTube so that the browser has no problem continuing to play it, even if the user browses another tab, or even closes the program and the smartphone screen will be extinguished. "Kiwi Browser" then displays a simple control panel for the movie just like any other music player for Android, also on the lock screen;
"Kiwi Browser" shows an icon informing you whether the page you are browsing is saved in your browser's tabs;
I am asking you to add these functionalities to the Opera House, because, as other artists show, it is possible!