Well, the good news is you can always jailbreak your Kindle to install KOReader which plays nice with Wallabag.
KOReader is basically a custom app that has much more integration and plug in compared to built in Kindle app.
Think of your current Kindle UI as "default app" and KOReader as another app that's much more powerful than Kindle app, and you can always switch between Kindle "app" and KOReader "app" at anytime so you don't even lose any built in Kindle functionality.
Personally I found KOReader to be super useful for these:
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Dark mode on Kindle Paperwhite 3 which doesn't support it natively
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Use gesture to increase or reduce Kindle backlight
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Connect to cloud storage to download books directly
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Download article using RSS for web serial (shoutout to Pale lights) and basically read my web serial in Kindle
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Set WiFi to be auto off when Kindle is sleeping and auto connect when out of sleep mode.