Be clear and concise when describing the problem. Be specific and remember to include important details, such as the exact error message or address of the site you're having trouble with.
Also see https://forums.opera.com/topic/26794/instructions-on-posting-about-problems-in-opera-for-android. It's valid for Touch as well.
Same thing here. I have the following connected via flow:
PC (Win 7 64)
Android (Ulefone Armor 2, stock Nougat)
Android (Samsung Galaxy Tab 2, custom Slimkat ROM)
Android (Samsung Note 3, custom Resurrection Remix ROM)
Everything works well in all directions, except Galaxy Tab, where I get the same effect as described by you. Actually it sends info via flow to other devices, where it appears properly and receives flow info from them, but it only appears as notification. My flow screen itself looks exactly as yours on the screenshot.
I'm afraid it might be device specific problem or some ROM glitch, probably difficult to pinpoint as it seems to work on on one of my custom ROMs and refuses to work on another.
And yes, adding flow to main Opera browser for Android would be nice.