Google Chrome Developer Tools - what is this?

Question

Is this some kind of a context? How is it created?

Google's Chromium source code has a webFrame which seems to create contexts which show up there. Are there other ways in which these can be created?

Any reference to code/articles on this is welcome.

Answer 1

According to the google tools description, this dropdown is used for selecting of execution context (the frame of the page you are working on).

You can find further explanation here, under the section "Selecting execution context":

https://developers.google.com/web/tools/chrome-devtools/console/