Long string not ended by EndPreamble

[Jean-Marc Lasgouttes]

Le 06/05/2023 à 14:06, lorenzobertini97 at gmail.com a écrit :
> Dear list,
> since at least a year I've been getting the following after validating
> a local layout in document preferences:

Do you managed to find the particular code that causes issues?

The way these long strings work is as follow:
* the first line determines the prefix, i.e. the sequence of spaces and 
tabs that are the start of string.This prefix is remembered and remove 
from the string.
* the lines that follow should begin with this prefix, which will not be 
kept in the strings.
* the first line that contains only the end token (and spaces/tabs) ends 
the parsing.

>> LyX: Long string not ended by `EndPreamble' [around line 4 of file
>> current token: 'EndPreamble' context: '']

I never saw this issue. Can you send an example file where this happens?

JMarc