Can't download some attachments

Kopano Core: 8.6.2 / WebApp: / Z-Push: 2.4.2+0-0 / UCS 4.3-1 errata217

Hi There,

I’m running into a problem: Some attachments can not be downloaded or previewed from webapp (in preview pane, tab nor external browser window). If i click the attachment or right-click and select ‘download’, nothing happens. Disabling the preview-plugin does not help.

Browser (FF 61.0.2 / 64-bits) console will show:

offsetParent is not set -- cannot scroll viewer.js:161:5
	scrollIntoView resource://pdf.js/web/viewer.js:161:5
	_scrollIntoView resource://pdf.js/web/viewer.js:6220:6
	_resetCurrentPageView resource://pdf.js/web/viewer.js:6698:5
	_setCurrentPageNumber resource://pdf.js/web/viewer.js:6390:9
	scrollPageIntoView resource://pdf.js/web/viewer.js:6708:7
	_setScaleUpdatePages resource://pdf.js/web/viewer.js:6645:7
	_setScale resource://pdf.js/web/viewer.js:6690:7
	set currentScaleValue resource://pdf.js/web/viewer.js:6442:5
	setInitialView resource://pdf.js/web/viewer.js:1689:7
	load/</< resource://pdf.js/web/viewer.js:1545:9
PDF 3e7e0d5f9c2f5b4f808c57da3b6870ce [1.5 Nuance PDF Create / SN18-038 Snijwerk 18.024 bestelling 02 rev-0.xlsm] (PDF.js: 2.0.491) viewer.js:1628:7

If there are more attachments i can download it as a zip together with the others though.

Is this a know issue?
What can i provide to debug/resolve this?

Kind regards.

We got also problems with attachments on 8.6.2, it works fine again since we updated to 8.6.7 .

Right, will have to wait until a new Kopano-Core package comes out for Univention to see if it also resolves my problem.