To plugin, or not to plugin, that is the question,
Whether 'tis nobler for the scripts to suffer
The slings and arrows of outrageous fortune,
Or to take arms against a sea of changes,
And by plugging in end them?
In the recent announcement for the Beta release of the new Stacks Editor, there is a roadmap item for adding support for external plugins. However, the item is scoped to adding support for extra native features specific to various sites of the Stack Exchange network.
When the Stacks Editor is eventually rolled out network-wide (and likely be made the default or even the only editor), it is naturally going to break a significant number of existing community integrations such as userscripts that have been developed with the old editor in mind.
It is expected that, as third-party developers, we will have to update them to work with the new editor, but the idea that there can be a stable public API for extending the editor capabilities is quite appealing (since it is also open source, it means that such extensions can even be integrated with the editor natively if they prove to be popular enough).
A public API for extending the editor via the plugin system is also in line with the announced project to provide a stable API for third-party integrations to hook into without constantly being on the lookout for breaking changes.
To summarise, are there plans to allow custom plugins for the new editor and, if by chance there are not, would it be considered a desirable community contribution as the project is open source?