I noticed that for some system apps (for example chrome, which is preinstalled by default on my device) I can't do
adb backup . Doing so results in the 47 bytes dummy .ab file. I checked in manifest they have
Eg for chrome this is:
allowBackup="true" backupAgent="org.chromium.chrome.browser.ChromeBackupAgent" extractNativeLibs="false" fullBackupOnly="false".
Why this is happening? How can I backup such apps' data without root? PS: Helium backup doesn't show system apps.