Allow persistent extensions

[Wrexthor]

Would be very helpful with ability to use extensions.

[Atinoda]

Thanks - this a timely issue! By coincidence I was thinking about extensions this morning, specifically how to install additional third party ones and how to modify the bundled ones. I will do something about it this weekend, need to think through a few different ways of handling that.

Would you mind describing your use case or thoughts in some more detail? I will bear it in mind when I'm thinking of solutions, and it would help to have another perspective as well to make sure the solution is generalised.