"JavaLoader error" in LibreOffice extension

I work some time without any problems, with Zotero and LibreOffice.
Today, Zotero calls me, I should install the extension for LO, though I have it installed already.
The installation over Zotero failed (I don't know the exact message anymore :( ).
Now, I want to install the LO extension manually, so I delete the old Zotero extension with the LO extension manager, and want to add the Zotero extension "Zotero_linux-x86_64/extensions/zoteroOpenOfficeIntegration@zotero.org/install/Zotero_OpenOffice_Integration.oxt".
But now, LO calls:
(com.sun.star.uno.RuntimeException) { { Message = "javaloader error - could not find class com/sun/star/comp/loader/JavaLoader", Context = (com.sun.star.uno.XInterface) @0 } }

I have delete Zotero and unpack it again, but no improvement.
Sign In or Register to comment.