tachiyomi-extensions VS TachiyomiSYPreview

Here

As the other commenter said, Tachiyomi is just the client. After installing Tachiyomi, you'll need to link/install the 3rd party sources that you want to read manga from. Tachiyomi calls them "extensions" and here is the full list of sources/extensions that are available.

If you haven't and you can't update extensions with the app closing all the time, you can proceed to the site to download.

Try to install directly: https://tachiyomi.org/extensions/

a bit techie tips: if you familiar with building apk, you can go to tachiyomi extension github, edit the user agent in source code here https://github.com/tachiyomiorg/tachiyomi-extensions/blob/master/src/all/mangadex/src/eu/kanade/tachiyomi/extension/all/mangadex/MangaDex.kt (remove tachiyomi part), build, install, and voila

Edit: I ask because this commit is mentioned in https://github.com/tachiyomiorg/tachiyomi-extensions/issues/12472 and was expecting it to solve some of the cloudflare issues

Extension requests go to the github extensions repo, but it has already been requested

This is looking really promising, I've tried most of the existing book/manga servers and didn't really like any of them for one reason or another (but usually because of bad UI/UX). Like someone else said already, Tachiyomi support would be amazing, I can't imagine reading manga any other way on Android devices. You can take a look at how the Komga extension works for reference.

If it has Android 5.0 or above, try out TachiyomiSY (only the preview version currently supports MangaDex Log In).

It's fixed in the latest version of preview, here's a link to the preview releases