#540 Set focus on info box when windows opens

[GodzillaXP]

When the MediaInfo windows opens and displays the information I would expect to be able to scrol down the info text with arrow keys and PgUP/PgDown.
But this does not work straight away.
Instead you have to click inside the text box with your mouse or hit Tab three times.

It would be better if the focus was on the text field from the beginning.

btw: I am not sure what that means for #525.
https://sourceforge.net/p/mediainfo/feature-requests/525/