bookTitleMarkup and tocItem cause empty page

[Simon Albrecht]

Hi Jean,

On 01/06/2022 15:24, Jean Abou Samra wrote:
> Please give an example.


I’ve gone debugging, and it’s a weird combination of two things that 
causes the empty page:

%%%%%%%%%%%%%%%%%%%%%%%
\version "2.23.9"

\paper {
  bookTitleMarkup = \markup {
    \vspace #.3
  }
}

\bookpart { \markup { 1 } }

\tocItem \markup "toc2"
\bookpart { \markup { 2 } }
%%%%%%%%%%%%%%%%%%%%%%%%%

I don’t understand… in my real-world book, the empty pages were empty, 
now in this tiny example the second bookpart appears to get duplicated, 
and this only because the bookTitleMarkup contains _anything_ other than 
empty \fromproperty calls. Even \markup\null as bookTitleMarkup has the 
bug (?) occurring.

Best, Simon