distortion of text in a texarea

Hi,

I sometimes see a strange distortion of text in a texarea
(see attached file, selected record and field B-Artikel Omschrijving)

It happens sometimes when you click in the emty space behind the text.

It looks like it happens more often when there are several short lines
in a text field. for instance :

aa
bb
cc

any one saw this before and found a solution ?

Regards,

Hans

distort.zip (280 KB)