Can't import into Zotero a BibTeX file exported from JabRef

Instead of importing the contents into Zotero, Firefox tries to Open/Save it itself. The fix was found in Zotero forums :

This seems to be related to the character/mime encoding of the BibTeX file. Zotero produces UTF-8 files & can import them without spawning a new window:
$ file Exported\ Items.bib
Exported Items.bib: Unicode text, UTF-8
$ file -i Exported\ Items.bib
Exported Items.bib: text/plain; charset=utf-8But not so with ascii files:$ file broken.bib
broken.bib: BibTeX text file
$ file -i broken.bib
broken.bib: text/plain; charset=us-asciiChanging the file to UTF-8 w/ BOM:$ uconv --add-signature broken.bib >fixed.bib && file fixed.bib
fixed.bib: Unicode text, UTF-8
$ file -i fixed.bib
fixed.bib: text/plain; charset=utf-8leads to successful import (as does importing from the clipboard).

But the fix did not work for me. So in JabRef, I had to export the same file into RIS from format. The RIS file imported successfully into Zotero.