Roundcube Attachments Not Opening in 1.6.0

[jgrata]

Some attachments such as Office documents, PDFs, image files, (not txt), do not open when using the Roundcube 1.6.0 webclient.  A popup window does open with the message "Loading data", but the file never opens.  The is happening on Firefox 116.0.2 and 115.0.3.

However, attachments do open on Chrome ver 115.0.5790.171.  Interestingly, Chrome seems to think the mailclient page is a deceptive site.

Any suggestions?