What Makes A Singletask Activity Have 2 Instances?

As per the docs, singleTask activities can't have multiple instances. The only activity of my app is singleTask, and it has 2 instances at the same time. Steps to recreate the issu

Solution 1:

An Android application can have multiple tasks. Each task can have multiple activities. singleTask and singleInstance control the behaviour of the activity (its uniqueness) inside the task, but it can happen that an App has two or more tasks with the same Activity inside.

This is what is actually seen here, an App with two tasks with an LauncherActivity inside, one for each tasks. As workaround, ensure that there is always one task in the app. On the LauncherActivityonCreate add:

val appTasks = getSystemService(ActivityManager::class.java).appTasks
if (appTasks.size >= 2) {
    appTasks.dropLast(1).forEach { it.finishAndRemoveTask() }
    appTasks.last().moveToFront()
    return
}