Option to only list downloaded versions of Electron in the dropdown

[miniak]

The list of Electron versions to the left of the run button shows way too many items. Make it possible to only display the downloaded versions, which would keep the list small. New versions can always be downloaded in the settings.

[malept]

I think if we were to do that, there should be a link to get to that settings page from the dropdown.

[felixrieseberg]

Alternative solution: I'll keep the default as it is, but we'll offer this configuration from the settings.

[felixrieseberg]

And done!