My KInfocenter shows: KDE Plasma Verson: 5.13.5 KDE Frameworks Version: 5.49.0 Qt Version: 5.11.2 Kernel Version: 4.18.0-1-armmp OS Type: 32-bit
About Falkon: Application version 3.0.0 QtWebEngine version 5.11.2 About Konqueror: Version 5.0.97 I made an apt-get upgrade yesterday and both Falkon and Konqueror browsers work now! I assume that the upgrade of QtWebEngine from 5.11.1 to 5.11.2 solved the problem. This bug can therefore be closed.