10.55.3 Can you answer these questions?

10.55.3.1 LuaLaTeX with polyglossia and biblatex

https://tex.stackexchange.com/landing/r/digest?cta=question&id=724605

I have the following minimal file 
\documentclass{scrreprt} 
\usepackage{polyglossia} 
\setdefaultlanguage[variant=austrian]{german} 
\usepackage[backend=biber]{biblatex} 
\begin{document} 
Hier steht ... 
[biblatex] [polyglossia]
 

asked by pchris https://tex.stackexchange.com/landing/r/digest?cta=user&id=334707 Score of 1

10.55.3.2 How to make boxed headers in imakeidx

https://tex.stackexchange.com/landing/r/digest?cta=question&id=724604

I am very interested in making my index headers look like those in this answer from 2017: Sample. The MWE from this answer is no longer available, so I was hoping to seek help in a new question. 
Here ... 
[indexing] [imakeidx]
 

asked by Jeremiah Stevens https://tex.stackexchange.com/landing/r/digest?cta=user&id=334710 Score of 1

10.55.3.3 Replicate a LSTM Cell

https://tex.stackexchange.com/landing/r/digest?cta=question&id=724687

Consider the following code: 
\documentclass{article} 
\usepackage{graphicx} 
\usepackage{float} 
\usepackage{tikz} 
\usetikzlibrary{matrix,chains,decorations.pathreplacing,arrows,calc, shapes,... 
[tikz-pgf]
 

asked by Murilo https://tex.stackexchange.com/landing/r/digest?cta=user&id=178497 Score of 1

answered by hpekristiansen https://tex.stackexchange.com/landing/r/digest?cta=user&id=8650 Score of 0