[Samsung Galaxy Note 9 Questions & Answers] Qui Peccavit:
Samsung not allowing logging into Samsung account on rooted phones

The exact same thing is happening to me after the last firmware update. On the old firmware, it was possible to log into one's SAMSUNG account to re-download previously purchased items from the Galaxy Store. Since the July 1st, 2019 security patch, SPAMDUNG have elevated their harassment of rooted customers to a new level:

Every time one tries to enter the user credentials (e-mail address and password for the Samsung account), the phone goes to the Legal Information page with the terms and conditions. After accepting them, a field at the bottom pops up, asking whether one would like to use biometrics for identification. No matter whether one chooses «not now» or «register», a black square appears between the two possible answers to the biometrics question, informing the user that «processing failed». Sometimes, the following error message is shown in the white field at the bottom of the screen ...

Account

Unknown error

(DataNull0/A300103)​

... before being taken back to the account settings with the field for the Samsung account's e-mail address and password. From there, one could play the scenario over and over again ad infinitum, but without any hope of ever getting out of this «login loop».

To make matters worse, as soon as one enters one's e-mail address in an attempt to log in, the Samsung Experience Service sends the following notification in 15 min. to 1 hour intervals, and they cannot be turned off in the configuration settings:

Samsung account

To continue using services securely, sign in again.​

When trying to «Continue with Google»:

To continue, sign in to your Samsung account again.​

The suggestions that one can find on the Internet to at least get rid of the nerve-killing notification messages are:

Settings | Developer Options | Running Services

Samsung Experience | Notification Listener | Settings | Notification Access

Samsung Experience => turn this off!!

Settings | Apps | ⁞ (upper right corner) | Show System Apps | Samsung Account => turn off Notific., uninstall updates

Navigate to http://findMyMobile.Samsung.com. Login, accept the terms & conditions, reboot the phone, voilà.

None of them work.

To disable SPAMDUNG Galaxy Apps notifications:

Open the Samsung folder and the Galaxy Apps therein.

Tap the ⁞ menu (three vertical dots to access more options) in the upper right corner.

Tap «Settings», then «Notifications» and slide the button to «off».

Samsung's notifications should now no longer bother you, but that does not solve the underlying problem.

This leads to the questions:

How to overcome the impertinence that SPAMDUNG harass their customers with and log into one's SPAMDUNG account on a rooted phone?

Alternatively, how to back up the purchased fonts, themes, etc., that were acquired from the Galaxy Store from an unrooted phone to an external SD card or Windows PC, in order to re-install them to the rooted phone later?

Thank you for any pointers to solutions that allow to update rooted phones every month, in a manner that preserves the software one has paid for as well as the configuration settings, apps, their data and so on.