it's about two days that I realized that I've got a strange problem on texteditor (gedit, but also Geany and others).

When I scroll the text (with mouse but also with page down/up) it didn't refresh properly.

Only after few clicks on it the situation return to normality.

All other things seems to work nicely (for example: scrolling text on LibreOffice it's not a problem).

It seems a GTK+ problem... but how to solve this issue?

Thanks a lot!

UPDATE:

It seems that Cairo-dock it's responsable of the problem. With only unity or gnome all works fine, when I launch Cairo dock (OpenGL or not is the same) then gedit and other editors slow on refresh.
Normally I use Cairo dock + Unity session. All worked fine and so I think that the problem starts with the latest update (some days ago).

UPDATE 2:

Trying to install other text editors... for example: X2 editor works fine with the same document that cause problems with gedit/geany.