Android apps install but never appear

REPRODUCIBILITY (% or how often): 100
BUILD ID = OS VERSION (Settings > About product): 4.1.024
HARDWARE (XA2, X10, X10 II, …): Xperia X
UI LANGUAGE:English
REGRESSION: (compared to previous public release: Yes, No, ?): Worked fine in early 3.x, just upgraded in two steps and problem appeared.

DESCRIPTION:

Returning to SFOS after a year or so away, I upgraded my SFOS. It took two upgrades. I reinstalled my applications, most of which had disappeared, including Android support.
To replace lost ones, I installed ProtonMail and Opera from what I think was Aptoide – the website, because the native application times out before starting; it’s a lot sketchier than I remember – and they did indeed make their way into the appropriate directory. Clicking on them from file manager opened the Android installation routine, which went nominally and appeared to succeed. But the applications never showed up among the other applications I have installed. The only Android-related application that I have that does function is FDroid.

PRECONDITIONS:

STEPS TO REPRODUCE:

EXPECTED RESULT: Working Android applications in launchable form.

ACTUAL RESULT:

ADDITIONAL INFORMATION:

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