Soft line breaks in new richtext widget

[delucis]

Describe the bug

In the new richtext widget, soft line breaks (shift + enter) do not emit a line break in the final Markdown. In the old markdown widget these would emit \ at the end of the line to force a hard line break, but the new widget doesn’t include this, causing many Markdown renderers (including Decap’s built-in preview) to ignore the newline.

To Reproduce

1. Open an item in the CMS that uses the richtext widget.
2. Add some text that includes soft line breaks (e.g. type while using shift + enter to break up your text)
3. Observe that no line breaks are shown in the preview pane
4. Observe that when saving the item, the Markdown output includes newlines but no trailing \.

Expected behavior

The editor should output \ at the end of soft line breaks like the markdown widget does. (Or an alternative like a <br> element.)

Screenshots

Here’s an example of soft line breaks in the editor and rendering without breaks in the preview pane:

Applicable Versions:

• Decap CMS version: 3.12.2
• Git provider: not relevant
• OS: macOS
• Browser version: Firefox 150
• Node.JS version: 24.15.0

CMS configuration
It’s a lot in my case, but here’s a relevant fields config:

		{
			name: 'body',
			label: 'Page contents',
			widget: 'richtext',
			buttons: ['bold', 'italic', 'link', 'heading-two', 'quote'],
			editor_components: ['image'],
			modes: ['rich_text'],
		},

[delucis]

I did a test to see what the raw value from each editor looked like using the following text:

Text
with
breaks

The old Slate data looks like this (checked in the handleChange() method):

{
	"type": "paragraph",
	"children": [
		{ "text": "Text" },
		{
			"type": "break",
			"children": [{ "text": "" }]
		},
		{ "text": "with" },
		{
			"type": "break",
			"children": [{ "text": "" }]
		},
		{ "text": "breaks" }
	]
}

And the new Plate data shape looks like this (also checked in handleChange() in the new implementation):

{
	"type": "p",
	"children": [
		{
			"text": "Text\nwith\nbreaks"
		}
	],
	"id": "-f_J1oq-ED"
}

So I guess the difference is that Slate treated these as a separate, semantic break node type, which are mapped to the equivalent mdast node in the slateRemark module whereas Plate just reports the newlines and the same logic in the richtext package is never hit.

As far as I can tell, there’s no way inside Plate to get it to represent newlines in this way, so if compatibility is a goal, the best approach might be to use a remark plugin like https://github.com/remarkjs/remark-breaks?