The new Release 20.03 is out! You can download binaries for Windows and many major Linux distros here .
It was an incorrect image size (32x32 instead of 22x22) and is fixed in trunk.It's the "doxywizard.png" and you can resize it yourself in "share/CodeBlocks/images/" below C::B's exe-folder (on windows).For a quick fix you can resize it yourself.