After uninstalling DuckDuckGo for Android, I decided to go with Brave for Android for it's experimental background video playback. However I noticed this on the NTP:
Yep. Shown on the second tab you open every time you launch Brave and every forth tab during that browsing session.
Standard background images are shown on every tab by default though.
Yes, and they seem to re-appear after updates or something, even when you change the setting. Android version needs work but it's OK for casual browsing. And it has brave://flags which I like.