1) Open Codeblocks
2) Open text file in codeblocks
3) Open the same text file in an external editor
4) Both editors have to be seen on the screen
5) Modify the text in the external editor and save
6) Click in codeblocks.
7) The reaload dialog appears, say reload yes
8) Random text is selected
See forum post for more detail:
forum
Diff:
This occurs in both Linux and Windows Code::Blocks SVN 12529 (SVN trunk built locally on both).