Insert Field > File name produces full path and file name.
Is there a way to insert file name (only as in Write)?
Insert the file name via menu Insert>Field command>File name. Right click on the field. Now you can choose what information you would like to have.
Sorry for the german-UI.
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Windows 10 Home; Version 1809; 64-Bit | LibreOffice, Version: 6.2.3.2 (x64)
My LO v6.2.1.2 does not have Field command’ under Insert.
It has Insert>Field>File Name. File Name is shown as a folder and right OR left clicking it inserts the full path and file name into the document.
Under Insert there is also >Form Control>File Selection, but this does not insert file name, but just an empty box.
It seems that the LO versions are different.
You can download the newer version of LibreOffice here.