This enables Electron's context isolation mode as recommended in their guidance.
We use the context bridge feature to regain access to only the IPC channels we
expect to have access to.
None of this will work as it will need tweaking (at the very least
I've not copied the origin migrator because that's had long enough)
but these are files which already existed in their current state and
so don't need re-reviewing.
Šimon Brandner