I am experiencing an issue with copying and pasting via Ctrl-C. Only menu->copy and right-click copy works fine. My problem is with the keyboard shortcut only. I checked to see if its assigned in the options, it is, but does not work. I also checked to make sure it does not occur with other applications (LibreOffice, Inkscape's text editor etc.)

OK - Highlighting with shift and cursor arrows, then Cltr-C then Ctrl-V into Qt-Creator works fine.
OK - Highlighting with the mouse and then middle-clicking into an external text-editor works fine.
OK - Highlighting with keyboard or mouse then menu->copy or right-click->copy then Ctrl-V to external editor works fine.

X - Highlighting with shift and cursor arrows, or mouse then Cltr-C then Ctrl-V into external text-editor does not work.