Differences concerning the htmlviewer between Windows and Mac

I am making a program that sometimes shows pictures and text and sometimes a html-viewer. I clean the window every time before making another combination. With Windows it works fine but on a Mac the screen covers part with the height and width of the previously used html-viewer. I cannot explain why this happens and how I can prevent it.

Any ideas or a concrete advise? Making invisible or reducing the size to 1x1 does not help.

normally you could load “about:blank” as URL to clear it.

I 'll give it a try, Christian,

Vielen Dank aus Holland :wink: