org-ascii-table-keep-all-vertical-lines

org-ascii-table-keep-all-vertical-lines is a variable defined in `ox-ascii.el'.
Its value is

nil

Documentation:
Non-nil means keep all vertical lines in ASCII tables.
When nil, vertical lines will be removed except for those needed
for column grouping.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.4 of Emacs.