Hover preview breaks when loading common packages

[LorentsL]

Environment

• TeXstudio: 4.4.0
• Qt: 6.4.1
• OS: Windows 11
• TeX distribution: texlive

Expected behavior

Expected to see the tooltip popup previews of mathematical formulas, in documents using luacode and loading microtype.

Actual behavior

When I switched to LuaLaTeX the previews couldn't compile properly. The problem occurs when loading microtype.

I tried the workaround of keeping pdfLaTeX just for the previews, but this does not work when loading luacode.

How to reproduce

Change the settings to Preview -> Command: Preview with lualatex. Make sure that the checkbox "Show preview as tooltip on formulas in editor" is ticked.

Minimal non-working example:

\documentclass{article}
\usepackage{microtype}
\begin{document}
	$A$ $B$
\end{document}

Hover over a dollar sign in $A$. The preview works as expected. Do the same with $B$. The preview doesn't show. The message "Process exited with error(s)" is displayed.

Similar problem (perhaps less surprising):

Change the settings to Preview -> Command: Preview with pdflatex. Minimal non-working example:

\documentclass{article}
\usepackage{luacode}
\begin{document}
	$A$
\end{document}

The preview doesn't show up. The message "Process exited with error(s)" is displayed.

[octaeder]

lua can make problems, f. ex. with tikz. In this case unset adv. option for preview as follows:

Of course this will slowdown preview depending on the size/amount of code of the preamble.

[octaeder]

For a description on how to find the temp files s. #2785.

The 1^rst case (with code given above) doesn't run with option precompile preamble. There is nothing we can do. So deactivate precompile preamble, then inline preview and tooltip preview work:

Details: Compiling with precompiled preamble shows messages like this:

File: mt-LatinModernRoman.cfg 2021/02/21 v1.1 microtype config. file: Latin Mod
ern Roman (RS)
[\directlua]:1: attempt to index a nil value (global 'microtype')
stack traceback:
	[\directlua]:1: in main chunk.
MT@ifstreq ...{microtype.if_str_eq([[#1]],[[#2]])}
                                                  endcsname 
l.111    }

The lua interpreter ran into a problem, so the
remainder of this lua chunk will be ignored.

The 2^nd case will succeed when switching to preview with lualatex. You can't use pdflatex here.

@sunderme From my point of view this issue can be closed.