There's still one area missing for custom extensions. This request is for the ability to create custom extensions (i.e. actions) for App Flows.
The idea is to be able to add custom extensions for actions like keytar for securely storing passwords and other sensitive data in Electron apps.
@kfawcett
Then why don’t you try creating a custom extension for App Connect?
My understanding is App Connect != App Flow. I need to build a custom action in the App Flow.
Yes, App Flow and App Connect are different things, but I mentioned it because maybe you can solve your problem faster this way. Perhaps you could also achieve your goal more quickly.
I need to process something inline of a flow (e.g. insert/retreive a value in OS credential storage). Even if I could create an app connect extension I don't believe it would help in regards to the flow.
Did you not get a result when you wrote a JavaScript code for this and called it within App Flow?
I haven't tried that, but I prefer to build a custom extension for the app flow, hence this feature request.
You could also try an App Connect custom formatter
Bump
Maybe maybe maybe? 
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bump!
And another one! 
And another one
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