You can find a good Searxng instance or run your own (it can also run on a RPi)

Anything that runs Android should run KoReader too - which IMO is still the best way to consume Wallabag content.

I have recently purchased a BOOX tablet with Android 14 and it works great with KoReader. But even my old Mobiscribe 1st gen with Android 7 was doing its job - it was too old for most of the recent Android apps, but KoReader works fine even on ancient Android versions.

blog:http content is usually dynamically managed via asynchronous requests.

Your best bet is to use the Network tab and filter the actual request made by the browser when it tries to expand the resource.