Tested on Samsung Galaxy S8 running Android 8.0 (Oreo).

Calling ShortcutBadger.isBadgeCounterSupported(context) returns true, but setting the badge has no effect. (This worked correctly before updating from Android 7.1 to Android 8.0.)

It seems that the Samsung launcher on Android 8.0 rather uses the normal Android 8 function for badges instead (coupling it to active notifications).

Data from "IsBadgeWorking?":

deviceModel: "SM-G950F"
deviceBrand: "samsung"
shortcutBadgerVersion: "1.1.18"
androidVersion: "8.0.0"
launcherPackage: "com.sec.android.app.launcher"
launcherVersionName: "9.0.01.84"
launcherVersionCode: "900106084"