Samsung is removing the ability to reassign the Bixby Button
Samsung is so committed to Bixby, its new virtual assistant, that it put a dedicated button on the Galaxy S8. But given that Bixby is only available in Korean and US English at launch, a large portion of the world will have a dedicated assistant that can’t actually help them (for a few months, at least). Thankfully, there was a way to remap the button to launch a different app.
The S8 has just arrived and isn’t available very easily. Since it’s date of manufacture, by the time you purchase the device, most of the times there is an OTA (over the air) Update which brings in a lot of fixes and enhancements. However, it seems that this time an OTA update is being used to rework how a certain feature on the device works, the Bixby Button. Apparently, this update is removing the ability to remap the Bixby Button.
A XDA recognized Developer, flar2 who has developed Button Mapper came across the change. Samsung has modified the system to consume the Bixby button’s key events before it reaches the Accessibility Services, making it impossible to remap the Bixby button (unless you root).
This is very disappointing for a large chunk of users out there because Bixby isn’t fully functional yet and there were many who weren’t too inclined towards using it in the first place. Having an option to cusomtise your phone the way you want is always welcomed, and in this case, Samsung is literally taking away an available liberty.
Source: XDA Developers