Ability to Edit Text in the Visual Preview in a Custom Component

Please can a feature be built that allows an editor to edit text in the visual preview in a custom component? I.e. click on the text in the preview and edit it directly there, not in a separate box.

We already have the option to toggle inline editing turned on, this doesn't work for custom components.

This is very high priority for us as there is a huge volume of content that needs to be manually created as part of the re-platform and it will take a lot more time and effort to do without this feature.