Plasma 5.9 comes with global menus

[cobito]

Today the first version of the year of Plasma 5 has been announced, successor to the first LTS that came out a few months ago and with some changes to take into account.

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[palotes]

The thing is that kde 4 was an environment written from scratch and many of the functions that had been introduced since kde 1 disappeared. In summary, kde 2 was a continuation of kde 1 and kde 3 was a continuation of kde 2 but kde 4 had nothing to do with the previous ones. Plasma 5 is a continuation of kde 4 so it is normal that functions that already existed in older versions appear. That's what free software has. When the environment becomes boring again as happened with kde 3, they will do it again from scratch and start over.