SUMMARY STEPS TO REPRODUCE 1. Open Marble (2.2.20 (2.3 development version)). 2. Open Legend. OBSERVED RESULT Legend only says 'Legend' and does not provide any information about the map (totally blank). EXPECTED RESULT Legend should show information about the map. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Linux (x86_64) release 5.4.0-58-generic (available in About System) KDE Plasma Version: 5.18.5 KDE Frameworks Version: 5.68.0 Qt Version: 5.12.8 ADDITIONAL INFORMATION
The Fedora package also has this issue, and has had it for a couple years now. I guess the Kubuntu package was also built without QtWebEngine support, because that is the issue on Fedora according to the build.log. (The build dependency in the package was never updated from QtWebKit to QtWebEngine when upstream switched.) So I think this is probably a downstream issue. I can fix the Fedora package, but you will have to contact the Kubuntu packager for Marble to get the Kubuntu package fixed.
That said, there is something upstream can do: it should only accept building without QtWebEngine support if it was explicitly disabled with a -D option, and not silently build a broken executable. That would have prevented this issue.
Adding the build-time QtWebEngine dependency to the Fedora package fixed it for me. You probably need to file a bug at Ubuntu Launchpad asking them to fix their package as well.
Indeed, the dependency is missing on Ubuntu/Kubuntu too: Compare: * bionic (18.04LTS) (old Marble version that still used QtWebKit) https://packages.ubuntu.com/bionic/libmarblewidget-qt5-28 depends on libqt5webkit5, * focal (20.04LTS) https://packages.ubuntu.com/focal/libmarblewidget-qt5-28 has no libqt5web* dependency (should depend on libqt5webengine5), * groovy (20.10) https://packages.ubuntu.com/groovy/libmarblewidget-qt5-28 is still missing the dependency, * hirsute (unreleased 21.04) https://packages.ubuntu.com/hirsute/libmarblewidget-qt5-28 is still missing the dependency. So this is a downstream packaging issue and needs to be reported to Ubuntu. And if anybody else is seeing this issue on any other distribution, it needs to be reported to that distribution as well.
Thanks for looking in to this Kevin, I have reported this on Launchpad as suggested. Kind regards, Fred