Kmail 5.4.3: Print wants to use 'WebEngine' via browser

[Maurice]

Running 64-bit Plasma  Mageia-6 on an HP 450 Probook (and on desktop PC), 
when I hit Kmail (5.4.3) 'Print' to print an email I see:

  "WebEngine printing is limited for the moment. An external browser will 
be used fo printing." and an option to select browser is offered 
(-->Firefox).

Printing from e.g. LO and Kwrite still uses HP5520 printer directly.

    How does one adjust to get kmail to do the same, as with e.g. Kmail 
4.14.5?
    
(Have never before seen such a reaction to Print...)

-- 
/\/\aurice 
	(Retired in Surrey, UK)     Registered Linux User #487649
		     Linux 64-bit Mageia-6:    Pan 0.140
    KDE Plasma5  Virtualbox 5.1.26   Firefox 52.2.0  Kmail 5.4.3