Chapter progress at any TOC depth
The chapter progress tokens now take a depth suffix, the same way %chap_title_1…%chap_title_9 already do: %chap_read_N, %chap_pages_N, %chap_pages_left_N, %chap_pct_N, %chap_pct_left_N, plus %chap_time_left_N and %chap_time_left_N_eta.
Without a number they track the deepest chapter, as before. With a depth, e.g. %chap_read_1, they measure against the top-level chapter instead. Useful for books with a very fine table of contents, where a plain %chap_read shows a tiny sub-section's length next to a top-level %chap_title_1.
Type them manually (they're not in the token picker). The README token reference lists the full set.