Preview: finding what's broken

[pglpm]

Hi everyone!

Moved to a new machine (Ubuntu 20.04), and after installing GNU Emacs (28.1, 
snap distribution: build 2, x86_64-pc-linux-gnu, GTK+ Version 3.24.20, cairo 
version 1.16.0), I installed several packages through package-list-packages. 
Including AUCTeX 13.1.3 (from the gnu package repository).

After restarting Emacs, everything works well, except that

• no Preview commands are available on C-c C-c,
• I see a "Preview" menu in the menu bar, but the command "Generate previews" there does 
nothing, but I see a "Quit" in the minibuffer.

I read

https://www.gnu.org/software/auctex/manual/preview-latex.html

and tried adding (load "preview-latex.el" nil t t) to my init file, but I get the error "No 
such file or directory" "preview-latex.el".

According to the manual "your installation is broken", and I'm trying to 
understand what's broken. I wonder if you can kindly give me some advice. Here are some 
things I've done:

• "M-x list-load-path-shadows" says "No Emacs Lisp load-path shadowings were 
found"

• Deleted any AUCTeX auxiliary directories and .el/.elc files in the directory 
where I'm working and in .emacs.d (*before* installing AUCTeX)

• Looked for "preview-latex.el" in .emacs.d: there's no such file. There's a "preview.el" 
and a "preview.elc" in .emacs.d/elpa/auctex-13.1.3/ though.

• So I tried (load "preview.el" nil t t) in my init file (restarting Emacs), 
but still nothing.

• Ghostscript 9.50 is installed on my system, and available on the command line (eg 
"gs -h" gives all GS info).


Anything else I should check?
Thank you!
Luca


AUCTeX info follows below (replacing my home dir with "****" for privacy)


Emacs  : GNU Emacs 28.1 (build 2, x86_64-pc-linux-gnu, GTK+ Version 3.24.20, 
cairo version 1.16.0)
 of 2022-06-24
Package: 13.1.3

current state:
==============
(setq
 AUCTeX-date "2022-04-16"
 window-system 'x
 LaTeX-version "2e"
 TeX-style-path '("~/.emacs.d/auctex"
                  "/home/****/.emacs.d/elpa/auctex-13.1.3/style"
                  "/home/****/.emacs.d/auctex/.auctex-auto"
                  "/home/****/.emacs.d/auctex/.auctex-style"
                  ".auctex-auto" ".auctex-style")
 TeX-auto-save t
 TeX-parse-self nil
 TeX-master t
 TeX-command-list '(("TeX"
                     "%(PDF)%(tex) %(file-line-error) %`%(extraopts) 
%S%(PDFout)%(mode)%' %(output-dir) %t"
                     TeX-run-TeX nil
                     (plain-tex-mode ams-tex-mode texinfo-mode) :help
                     "Run plain TeX")
                    ("LaTeX" "%`%l%(mode)%' %T" TeX-run-TeX nil
                     (latex-mode doctex-mode) :help "Run LaTeX")
                    ("Makeinfo" "makeinfo %(extraopts) %(o-dir) %t"
                     TeX-run-compile nil (texinfo-mode) :help
                     "Run Makeinfo with Info output")
                    ("Makeinfo HTML"
                     "makeinfo %(extraopts) %(o-dir) --html %t"
                     TeX-run-compile nil (texinfo-mode) :help
                     "Run Makeinfo with HTML output")
                    ("AmSTeX"
                     "amstex %(PDFout) %`%(extraopts) %S%(mode)%' %(output-dir) 
%t"
                     TeX-run-TeX nil (ams-tex-mode) :help "Run AMSTeX")
                    ("ConTeXt"
                     "%(cntxcom) --once --texutil %(extraopts) %(execopts)%t"
                     TeX-run-TeX nil (context-mode) :help
                     "Run ConTeXt once")
                    ("ConTeXt Full"
                     "%(cntxcom) %(extraopts) %(execopts)%t" TeX-run-TeX
                     nil (context-mode) :help
                     "Run ConTeXt until completion")
                    ("BibTeX" "bibtex %(O?aux)" TeX-run-BibTeX nil
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode context-mode)
                     :help "Run BibTeX")
                    ("Biber" "biber %(output-dir) %s" TeX-run-Biber nil
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode)
                     :help "Run Biber")
                    ("Texindex" "texindex %s.??" TeX-run-command nil
                     (texinfo-mode) :help "Run Texindex")
                    ("Texi2dvi" "%(PDF)texi2dvi %t" TeX-run-command nil
                     (texinfo-mode) :help "Run Texi2dvi or Texi2pdf")
                    ("View" "%V" TeX-run-discard-or-function t t :help
                     "Run Viewer")
                    ("Print" "%p" TeX-run-command t t :help
                     "Print the file")
                    ("Queue" "%q" TeX-run-background nil t :help
                     "View the printer queue" :visible TeX-queue-command)
                    ("File" "%(o?)dvips %d -o %f " TeX-run-dvips t
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode)
                     :help "Generate PostScript file")
                    ("Dvips" "%(o?)dvips %d -o %f " TeX-run-dvips nil
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode)
                     :help "Convert DVI file to PostScript")
                    ("Dvipdfmx" "dvipdfmx -o %(O?pdf) %d"
                     TeX-run-dvipdfmx nil
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode)
                     :help "Convert DVI file to PDF with dvipdfmx")
                    ("Ps2pdf" "ps2pdf %f %(O?pdf)" TeX-run-ps2pdf nil
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode)
                     :help "Convert PostScript file to PDF")
                    ("Glossaries" "makeglossaries %(d-dir) %s"
                     TeX-run-command nil
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode)
                     :help "Run makeglossaries to create glossary file")
                    ("Index" "makeindex %(O?idx)" TeX-run-index nil
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode)
                     :help "Run makeindex to create index file")
                    ("upMendex" "upmendex %(O?idx)" TeX-run-index t
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode)
                     :help "Run upmendex to create index file")
                    ("Xindy" "texindy %s" TeX-run-command nil
                     (plain-tex-mode latex-mode doctex-mode ams-tex-mode
                      texinfo-mode)
                     :help "Run xindy to create index file")
                    ("Check" "lacheck %s" TeX-run-compile nil
                     (latex-mode) :help
                     "Check LaTeX file for correctness")
                    ("ChkTeX" "chktex -v6 %s" TeX-run-compile nil
                     (latex-mode) :help
                     "Check LaTeX file for common mistakes")
                    ("Spell" "(TeX-ispell-document \"\")"
                     TeX-run-function nil t :help
                     "Spell-check the document")
                    ("Clean" "TeX-clean" TeX-run-function nil t :help
                     "Delete generated intermediate files")
                    ("Clean All" "(TeX-clean t)" TeX-run-function nil t
                     :help
                     "Delete generated intermediate and output files")
                    ("Other" "" TeX-run-command t t :help
                     "Run an arbitrary command")
                    )
 )