Keyboard won't save input language preference

[allhavebrainimplantsandmore]

Software Versions

• Python: 3.8
• OS: Android 5.0.1, Keyboard: Swift (tested Android native keyboard on Android 7.1.1, language preferences saves fine)
• Kivy: 2.0.0rc4
• Kivy installation method: Pycharm

Describe the bug
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Request keyboard to enter text into a textinput widget. Change keyboard language from English to 'something else'. Defocus textinput. Keyboard released.

Request keyboard to enter text again into the same textinput widget. Keyboard language is English. Need it to stay 'something else' until manually changed.

I tried this in my kv file for the textinput widget: text_language: 'ru_RU' but that didn't seem to work.

As noted in the header, I can reproduce this on Android 5.0.1 with Swift Keyboard. Native AOSP keyboard on AOSP 7.1.1 saves language preference just fine.

Expected behavior
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Keyboard input language should stay the same between text input within the app, like in all Android apps.

To Reproduce
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See description above.

Code and Logs and screenshots

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Additional context
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