It is indeed impossible to manually set the master file (with C-c _) to anything different from the local file.
When I remove the hook turn-on-window-margin-mode, from .emacs REFTeX resumes working normally.
Roberto Zamparelli
roberto.zamparelli@unitn.it===============================================
In GNU Emacs 26.3 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.22.30)
of 2019-10-22 built on lgw01-amd64-031
Repository revision: f244eb1dedaebcf69ad82bc28187cdb85a2986de
Windowing system distributor 'The X.Org Foundation', version 11.0.11906000
System Description: Ubuntu 18.04.3 LTS
Recent messages:
Loading /home/roberto/.emacs.d/elpa/auctex-12.1.0/style/article.elc...done
Loading /home/roberto/.emacs.d/elpa/auctex-12.1.0/style/babel.elc...done
Loading /home/roberto/.emacs.d/elpa/auctex-12.1.0/style/english.elc...done
Applying style hooks...done
Applying style hooks...done
Type ‘C-c C-l’ to display results of compilation.
LaTeX: successfully formatted {1} page
Making completion list...
Quit [2 times]
Mark saved where search started
Configured using:
'configure --prefix= --prefix=/snap/emacs/current/usr 'CFLAGS=
-I/build/emacs/parts/emacs/install/usr/include' 'CPPFLAGS=
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-L/build/emacs/parts/emacs/install/lib/x86_64-linux-gnu
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Configured features:
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Important settings:
value of $LC_MONETARY: it_IT.UTF-8
value of $LC_NUMERIC: it_IT.UTF-8
value of $LC_TIME: it_IT.UTF-8
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Major mode: Emacs-Lisp
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diff-auto-refine-mode: t
pyvenv-mode: t
shell-dirtrack-mode: t
recentf-mode: t
cl-old-struct-compat-mode: t
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transient-mark-mode: t
Load-path shadows:
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Memory information:
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