Plasma 5 Various Sep 27 2017
Score 67%
33 Dislikes
Qalculate 0.4 Plasma 5 Various
Score 67%
33 Dislikes
Sep 27 2017
I uploaded a new experimental version to github which should support libqalculate v2.0.0 much better. Sep 25 2017
Are you sure this issue is related to the plasmoid? I have upgraded two different machines to libqalculate 2.0 and both are working fine.

You can use "plasmoidviewer --applet org.kde.plasma.qalculate" to run it separately from KDE and see some debug messages in the konsole. Sep 08 2017
This issue has been fixed in v0.2.1. May 09 2017
Using an input box as a widget seems to be rather difficult and not
properly supported by KDE. I will look into making the icon
configurable. Oct 17 2016
You probably are missing the Extra CMake Modules (ECM) package.
Just search your package manager for "ecm" or "extra cmake modules" and the
installation should be pretty easy and straightforward.
Oct 17 2016
I just added install instuctions to the description. If that doesn't work for you please let me know. Oct 01 2016