Adding custom buttons to titlebar

[Rave]

I've seen software which added custom buttons to menu bar (like e.g. popular in Linux apps and DEs "rolldown" button - you know, the one who minimizes/unminimizes window, but leaves out title bar) and some other (but those were specific use cases, like in some Stardock apps).

Is there any way to do this in Lazarus? I'd like multiplatform solution which doesn't require me to make "custom title bar". I know I can do this, but would prefer not too, so my app would have consistent look with other apps on OS it is ran on.

[Dibo]

I doubt that there is multiplatform solution. On windows you probably find some API for that and call it from windows unit, but on linux it is more complicated due to multum windows decorators. I didn't see any program on linux which could add custom buttons on title bar. For example, opera and firefox which have custom button on windows versions, on linux they provide own title bar, so I supose that this is not easy on linux.