[Meta] Standalone text embed for dashboards

[poffdeluxe]

Related to #46341

Milestones

This meta issue is to track work around a standalone text embeddable for markdown and rich text for dashboards. Currently, dashboard depends on a markdown visualization for text on dashboards. This means that when adding text to a dashboard, a markdown visualization is added and then you must leave the dashboard and edit the text from the Visualization editor.

Phasing:

• New, simple text embeddable that renders markdown. This embeddable is only editable via the in-line editor
• Evaluate and select a simple rich text editor ideally one that outputs markdown behind-the-scenes but allows the user to style text without having to use markdown
• Add the new rich text editor to the in-line editor the text embed
• Unify the text embed with the markdown element in Canvas (Future)
• Add features that exist in the TSVB markdown editor (templating with data like canvas, backgrounds, colors) (Future)

Next Up

• Text embeddable with markdown support using the in-line editor (replaces existing text embeddable)
• Deprecate/remove old markdown viz
• Evaluate and select rich text editor
• Integrate rich text editor into text embed

Future Work

• Unify new text embeddable and Canvas markdown element
• Incorporate features that exist currently in the TSVB markdown editor

Deployment

I recommend that the first version of the new text embeddable should be deployed with the first version of the in-line editor. The reason for this is that the inline editor is a requirement for this project.

[elasticmachine]

Pinging @elastic/kibana-presentation (Team:Presentation)

[poffdeluxe]

EUI provides a simple markdown editor: https://elastic.github.io/eui/#/editors-syntax/markdown-editor

Here are a few interesting external editors to look at as well:

Editors with markdown:

• https://uiwjs.github.io/react-md-editor/
• https://github.com/outline/rich-markdown-editor
• https://simplemde.com/

Editors without markdown:

• https://www.slatejs.org/examples/richtext
• https://draftjs.org/

I think there's a conversation to be had around whether we want to have rich text without markdown and potentially allow this embeddable to operate in markdown mode (we give them the simple EUI markdown editor) or a different rich text mode that would not be markdown but might include other features

[ThomThomson]

Nothing here that we've had a request for math support in our markdown component, could be a later addition to this project.

[ThomThomson]

Closing this in favour of #46341 because that issue has more design discussion.