I’d like to remove ALL the tabs stops in the document. I’ve tried in Paragraphs and Style, but they remain. It’s irritating.
Please edit your question to mention your OS and LO version. Also describe what you’ve attempted.
You can remove custom tab stops but you can’t remove default tab stops. Custom tab stops are defined in the paragraph styles (or in the ruler in case of direct formatting). Default tab stop is set in Tools>Options, LibreOffice Writer>General
Are you talking about real tab stops, those inserted by pressing the TAB key? Then open the search&replace tool with Ctrl H, type \t in the search box and leave the replace box empty, under More options select “Regular expressions” and then press “replace all.”
If you are talking about first line indents, maybe they are set in the paragraph style level or as direct formatting, in that case they are not “real tab stops” so please, provide more information and perhaps a sample document that show the problem (a real document, not a screenshot).