not modify the set instance returned by this call. The consistency of the stored data is not guaranteed if you do, nor is your ability to modify the instance at all." Lint prevents you to write not working code https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-stu dio-main:lint/libs/lint-checks/src/main/java/com/android/tools/lint/checks/Shar edPrefsDetector.kt