Keyboard switching option greyed out in app

[AIVAS001]

Device: Samsung Galaxy A5 (SM-A520W)
OS: 8.0.0
App version: 1.09a-r3
Plugin version: 1.0.5
Adb version: Android Debug Bridge version 1.0.32 Revision eac51f2bb6a8-android
PC OS: Microsoft Windows [Version 10.0.19043.1110] 21H1

Plugin doesn't show in app plugins (normal?). Running plugin and performing test says plugin is configured correctly.
Doesn't matter if database open or not, app always has Keyboard switching option greyed out.
Plugin and/or app installed to external or internal memory doesn't matter - same result.
Exiting Adb shell before or after attempting to change app setting doesn't matter - same result.
Disconnecting device from USB after exiting Adb shell but before or after disconnecting from USB doesn't matter - same result.

(Instructions need to be updated slightly? "Keepass2Android > Settings > App Settings > Password-Access > Keyboard switching" is "Keepass2Android > Settings > App Settings > Password entry Access > Keyboard switching" on my OS.)

Other plugins installed, and functioning normally: QR Plugin 1.0.1, AutoFill-Plugin (Accessibility Service) 1.02.

I'm at a loss. I've tried everything I can think of.