I’ll throw in SWAG as another option which I found was easiest to setup, albeit it on a VPN/local only setup. It supports certbot for SSL and pre-defined proxy configs for various services (mostly linuxserver.io containers but there are others) and it’s easy to edit them to make your own configs. I’m not sure about portainer support as I’m not familiar with that.
I like how easy Shiori is to install and the UI is much more responsive than Wallabag (could be a config/install issue) but it does have some annoyances too:
But it is actively developed and it’s the most promising alternative to Wallabag in my view.