There has been some changes to the layout of Select and ComboBox in recent maintenance releases, so I would suggest that you first verify that your widgetset is up to date and that you are not getting old versions of the theme css files from your browser cache.
It sounds quite interesting that removing the nowrap property should stop the button from wrapping… Does this happen with any of the built in Vaadin themes or are you using your own theme?
There is also at least one known bug where the button wraps to another line, but your description does not sound like
#7013 .
I checked the widgetset and the browser cache and there was no problem. I also uses different themes (chameleon, runo, base) but the problem was always the same. IE and Safari work fine but firefox wraps the button!
is there anything else I can check to get the problem solved? Now i use NativeSelect to avoid the wrapped button, but I am missing some features like reducing the entries while typing.