There is a new issue since Version 7.4:

If I want to printout a single transaction-row of telebanking, automatic logout is done for reason: time-logout or different tabs are simultainiously open, etc. In Version 7.3 everything works as expected.
But other printouts on same web-page (e.g. summary over all) works.

But there is an difference between printing single transaction-row and summery-print-out:
In first case it opens a new tab with data to print-out, showing a further printer-Icon for real print-out (goes then to Wayfarers printing-view with printer-options).
Wayfarer 7.4 opens this page, but does a logout (without showing any data to print). Wayfarer 7.3 shows correct data and let me do an normal print-out via Wayfarers printing-view-page..

In second case (printing summary) both versions of Wayfarer jumps directly to printing-view and print out correctly.

What I can say: There was no change in code on tele-bankimg-portal (asked therefore). Tried it also with different spoofings - no luck.
At moment I have to switch back to V7.3 to do tele-banking.