NativeSelect.setEnabled(false) browser compatibility

In our application we set widgets to disabled when use of them does not make sense in a given context. Today my colleague complained that a combobox (actually a NativeSelect) in our app doesn’t grey out when setEnabled(false) is called - it correctly ignores clicks, but it does not grey out.

But when I tried it on my machine (Mac, with Safari), it did show greyed out. Suspecting a browser incompatibility, I asked her what she was running (Chrome) and whether the problem occured on her Firefox or IE browsers. It works as expected in those browsers. I tried Chrome (same version) on my machine - and it worked! So, Chrome version 39.0.2171.71 on a Mac works, but on Windows 7 box, it does not.

Since we were running a pretty old version of Vaadin (7.1.5), I upgraded to the latest (7.3.5) and tried again - same result.

Has anyone else noticed this? Should I be filing a bug against Vaadin or is this a Chrome-on-Windows issue?

Thanks for all info,
Tom