9.35.3 Can you answer these questions?

9.35.3.1 Error occurs when \usetikzlibrary in l3 style class file

https://tex.stackexchange.com/landing/r/digest?cta=question&id=687084

I have a class file which is simplified as follows: 
% mwe.cls 
\ProvidesExplClass{mwe}{2023/05/29}{0.1}{class file for writing mathematical exercises} 
\LoadClass{report} 
\RequirePackage{tikz} 
\... 
[errors] [expl3] [tikzlibrary]
 

asked by Stephen https://tex.stackexchange.com/landing/r/digest?cta=user&id=241621 Score of 1

9.35.3.2 Clipping using path defined as nodes

https://tex.stackexchange.com/landing/r/digest?cta=question&id=686866

I am representing sets using ellipses and would like to draw the difference between two sets: B - A (blue area in the figure below). 
Please consider the following code: 
\documentclass{article} 
\... 
[tikz-pgf]
 

asked by Antonio Sesto https://tex.stackexchange.com/landing/r/digest?cta=user&id=25883 Score of 1

9.35.3.3 Do you break typing conventions when typing LaTeX?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=686542

Sorry if this isn't relevant, I thought this might be a good place to ask about this. 
I am trying to improve my typing (specifically in the numbers row) so that I can type LaTeX faster, but I am ... 
[keyboard]
 

asked by S.L. https://tex.stackexchange.com/landing/r/digest?cta=user&id=254421 Score of 1