Top of header height

Wassup !

Easy question. I created an html_top_of_header and using the importing parameter (i_html_height_top) I defined the size 30.

My question is: There is a way to make it "freeze". In other words, after alv load the user can not change the size of top of header using the drag and drop tool.

Thx.

Usefull answers are always rewarded !