SUMMARY When pasting something into the notes plasmoid, it preserves the style of the pasted text. This is IMHO undesirable for notetaking, but more importantly, it also preserves foreground and background color, which is then impossible to change, and may make the text unreadable. As a workaround you have to paste everything into a text document first. SOFTWARE/OS VERSIONS Linux/KDE Plasma: openSUSE Leap 15.1 (available in About System) KDE Plasma Version: 5.12.18 KDE Frameworks Version: 5.55.0 Qt Version: 5.9.7
This is fixed as of Plasma 5.17! :)