- Had a parent project with two milestones - Hid and unhid a normal column (got normal dialogs).
- Observed the column options no longer being available for those columns.
- Archived one of the milestones and verified that it only appears when "Show Hidden Columns" option is on.
With "Show Hidden Columns" off:
{F1102691}
With "Show Hidden Columns" on:
{F1102696}Hid and unhid a milestone column (got "archive project" dialogs, underlying project archived/unarchived, column vanished).