pdfslicer VS GmsCore

They don't have to be! PDF Arranger or PDF Slicer will do this for you much more easily than PDFsam would:

https://github.com/pdfarranger/pdfarranger

https://github.com/junrrein/pdfslicer

If you just want to add another page I recommend to use another tool like PDFSlicer or PDFArranger.

You could also look at how other people and organizations have implemented GitHub Pages in their projects. For example, PDF Slicer has a master branch which houses the code for their application, and a gh-pages branch which houses the code that produces the documentation website. You can also have a repository/branch that exists solely to create a GitHub Pages website like this Picross page.

Is anyone here daily-driving microg and can share their experiences? https://github.com/microg/GmsCore/wiki/Implementation-Status does not exactly inspire confidence.

...will need to be rewritten to avoid Google Play Services.

Not true.

All that needs to happen is for open source developers to "re-implement Google’s proprietary Android user space apps and libraries".

https://microg.org/

microG itself connects directly to Google: https://github.com/microg/GmsCore/wiki/Google-Network-Connec...

No shit, of course they do.

>In general, we obviously try to minimize the connections to Google, but some services strictly rely on them and would just not work without.

What exactly do you think they should do instead?

MicroG

In release notes for GmsCore v0.2.29.233013 (https://github.com/microg/GmsCore/releases/tag/v0.2.29.233013), I also see:

Yes, the Xposed module is one way. There are also other ways

Which one should I use? Is this MicroG's official website right? (https://microg.org/)

Have a look into https://microg.org/ . Revanced yt uses a fork of GmsCore for its non-root install, though you still have to log in with a google account.