Some strange blue spots appear in my status line as I scroll or edit a buffer.
These spots are cleared after a <C-L>.
My lazyredraw option is off.
Here is a pic of the disturbance :

The status line is the vim-airline plugin and the font is Anonymous from powerline-fonts.
How could I set up an auto <C-L> of my status line after a move or an edit ?
The command :redraw does not clear my statusline ; only <C-L> does.
Thanks.