Deleted by mistake? Nothing is lost.

You can reach it in three ways, from every page. Right after a deletion, the message offers an "Undo this deletion" link. The bin icon at the top right shows how many items can be recovered. It is also in the Tools, Recycle bin menu. If you want a tab in the top bar, you can turn it on in the module settings.

No. The invoice comes back with its lines, extra fields, categories, links and attached files. Its payments, accounting entries and stock movements do not come back. The check screen reminds you of this before you confirm.

They stay 30 days by default, and you can change this for each record type. An automatic purge runs every day and erases what is past the delay. You can also empty the bin by hand.

The module captures deletions made through Dolibarr. It does not see those made directly in SQL, or by a module that bypasses Dolibarr triggers, and the settings page lists the installed modules in that case. Some types are not covered yet, such as supplier documents, members, shipments, contracts, expense reports and tickets.