Dear Mr. Berglund and Coppola,
Thank you for your response.It seems that we have to set those heights manually, unfortunately. Fujimaki
On Monday, September 16, 2019, 10:22:37 AM GMT+2, Bo Berglund via lazarus wrote:

Salvatore Coppola wrote

Ok it is a workaround but why not call your function only one time at start for instance in main form create?

Yes, a typical workaround...
I am so used to using OnShow since my form always is only shown once and never hidden afterwards. But you are right that it should rather be in OnCreate!