PyGObject - context menu

[<c buhtz posteo jp>]

Hello,

it is unclear for me how I should create and use context menus (by
right clicking with mouse).

There are a lot of outdated or C-based examples on the web. Also the
documentation has a lot of "popup" elements but marked them as
deprecated.

I opened a StackOverflow question for it with example code and a
screenshot.

https://stackoverflow.com/q/54847454/4865723