[Done] PB v6.xx ToolBarHeight on Linux

[mk-soft]

ToolBarHeight returns the wrong height.
As with macOS, it should always return the height NULL that the client window starts below the ToolBar.
This means that the output in the FormDesigner is incorrect.

[Fred]

Fixed.

[mk-soft]

I am currently working on the PureBasic FormDesigner.

Setting ToolBarHeight(...) to zero was not a good idea.
The height of the toolbar is needed to calculate the internal height of the window, as WindowHeight(...) returns the height including the toolbar.

It is therefore better to create the FormCode so that the position Y for the content is without the ToolBarHeight (as I already do with the IDE patch for v6.21).

So back to the previous ToolBarHeight method...

Sorry