Why keep them separate?
A drawing may have several working edits before the next formal issue. Do not turn every save into a new issued revision or treat a working version as an approved construction document. Record the sheet number, issue purpose and received or issued revision alongside the working history.
What happens when a drawing changes in chat?
Requested drawing edits can apply without a separate approval click in the current app. Review the result, use the available history or revert controls where appropriate, and resolve assumptions before issuing. Automatic application of an edit is separate from engineering sign-off and from confirmation to send an email.
Which version should you send?
Check the selected sheet and source against the intended formal issue. Review the export, title block, references and any outstanding comments, then record what was sent and to whom. A restore or working save does not by itself change the formal issue fields.