Somehow I accidentally deleted a column of tasks last night with an errant key strike - such a surprise!
Warning users when they’re about to delete a column that contains tasks would be nice. That or allow restoring to a prior column/to do list version (and not forcing the whole project to be copied).
If you immediately realise your mistake, you can (Ctrl-Z on a PC). You can also go to a prior version as shown below:
You can either restore to that version, and continue using that, or you can copy what you need from the history to your current doc.
Unfortunately, Coda has no way of knowing whether a column contains “tasks”, or any other important info.