After upgrading OnlyOffice Document server to 7.0.0, document attachments in XWiki cannot be saved, and all edits are lost. When a user tries to save a document, the error "Failed to save the page. Reason: Request error [downloading]" appears briefly at the bottom of the page. The browser dev tools shows an error 404 trying the reach the page "[object%20Object]" after click the save button.
Downgrading to OnlyOffice Document server 6.4.2 allows users to save documents again.
XWiki version: 14.0
OnlyOffice connector version: 1.6