I have done some work on this and it should be aligned in the latest version (2023-07-17.15, git commit 64c51c055836b9980).
Thanks Gavin. It looks fine now. I appreciate your doing this. I couldn't remember if it ever aligned either :). Another (separate but sort of related) problem that has been in texinfo.tex from the beginning is that the toc does not align correctly when there is 10+ sections (at any level below chapter). I remember noticing this in 1985 or so but never getting around to fixing it :). It didn't seem right to just always leave enough space for a two-digit section number, since few documents have so many sections. But if any sectional unit within a given chapter has >=10 items, I think all should be typeset with the two-digit spacing, else it would look weirdly wrong. Because of the way toc's are formatted with texinfo.tex, with big divisions between chapters, I think it would look best to do the >=10 check per chapter, but doing it for the whole document is also a viable option. Here's an example. The title "subsec10" is indented more than "subsec1" through "9", which is definitely wrong. "subsec21" is indented at the same level as "subsec1"..9, but IMHO it should be indented at the level of "subsec10" like all the other subsecs. The same happens at @section and @subsubsection levels. If you don't feel like working on it, clearly life goes on :), but it seemed an opportune moment to mention it. --thanks, karl.
secmany.texi
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secmany.pdf
Description: Adobe PDF document