This is the command invoked repeatedly to make the changes:
:%s/^\(.*\)|\%(\*\(\d\+\)\)\?$\n\1|\%(\*\(\d\+\)\)\?$/\=submatch(1)..'|*'..(max([str2nr(submatch(2)),1])+max([str2nr(submatch(3)),1]))/g
Problem: Visual highlight is inconsistent on a folded line with
treesitter foldtext.
Solution: Don't added Folded highlight as it is already in background.
Problem: When using treesitter foldexpr,
* :diffput/get open diff folds, and
* folds are not updated in other windows that contain the updated
buffer.
Solution: Update folds in all windows that contain the updated buffer
and use expr foldmethod.
