Suggest more graceful failure to save .csv worksheets

Using LibreOffice Version: Calc
I guess everyone except I knows that one cannot save multiple worksheets inside a .csv file (unlike a spreadsheet). I just learned the hard way after editing a file for several hours. So all my work is lost. My fault.

What fooled me was that I was able to save versions of the .csv file in different worksheets, so I thought I was backing up along the way. LibreOffice pleasantly allowed me to save the different worksheets, and displayed the worksheet tabs and names at the bottom the same as if it were a spreadsheet file. But when I closed and reopened the .csv file, all the worksheet tabs were gone, along with hours of work and my sanity.

So this is a feature request. To prevent others from repeating my mistake, perhaps have LO fail faster and more gracefully, such as refusing to save a separate worksheet and offering a warning. Thank you for your consideration.

Would you accept the assumption that no software can “gracefully fail” without any damage on every error made by users who did not adopt the basic information about the means they try to apply (in this case the export into a csv formatted file)?
(I agree that this proceeding should be listed under ‘File’>‘Export…’, and that offering it under ‘File’>‘Save As…’ is gravely misleading. However, any software user must know that deception is the standard and clear guidance the exception.)

@anon87010807: I reopened the thread becasue the deception caused by offering export to csv under ‘Save As…’ and allowing the suppression of the alert seemed on topic.
At everybody: A kind of “default menu structure” was created by MS software about 30 years ago. It is deceptive with many respects as also are the UI properties and the help texts of Windows from the beginning.
Users coming from MS office (e.g.) will expect to find the familiar structure nonetheless.
“Right or wrong - like MS!”

Feature requests are filed at - that seems unintuitive, but that’s how it is. Please consult for more information about this Ask board.

Thank you for the prompt reply. I filed a bug report here:

There is an alert warning you if you try to ‘Save As…’ Text CSV and prompting you for a decision.
There is also a checkbox allowing you to deselect the popup.

If you erroneously suppressed the alert, you can reinstate it under ‘Options’>‘Load/Save’>‘General’.