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Same issue here with S10e... Wallpaper scrolling worked until April update ☹️
....and it's the same after the One UI 2.1 May 1 security patch...No wallpaper scrolling. Samsung is simply not listening to its customers. Their line of thought must be "What's the point of using a 3rd party launcher if you can't scroll freely your wallpapers?"...It's not like the default Galaxy Launcher allows it and, to be frank, it has never been better than...anything elese out there. Stupid move, Samsung. And time for me to move to another brand.
Yes please fix this Samsung. Samsung lately has been doing more and more things that make me want to buy a different phone. My first Samsung was an S7 Edge, then I went to an S8, then S9, now a Note 10+. I've always defended my love for Samsung against my friends who always tell me to buy OnePlus or Pixel, but if Samsung doesn't stop doing stuff like this or throwing unwanted ads on a $1500 phone (https://www.androidpolice.com/2020/07/04/ads-are-taking-over-samsungs-galaxy-smartphones-and-im-fed-...) I might have to finally take my friends' advice.
wallpaper scrolling came back with Android 11/one ui 3.0. I have just installed it on my s10+ and it's certainly back. Samsung surely took their sweet time to bring back a functionality that should have never been left out in the first place.
Same for S10e. Once it has updated to Android 11/ONE UI 3.0, the wallpaper horizontal scroll is back. Thank you!!