Empty blocks are lost when performing an undo operation

[juanhurtado10]

Context

https://user-images.githubusercontent.com/20125027/129673632-f1ec0d96-123f-46b2-b1b7-fc32fbe5089c.mov

[komaldembla]

Please find the list

Device, Browser, OS:

• Macbook Pro, Chrome (92.0.4515.107), MacOS Catalina

Editor.js version: 2.22.0

Plugins used with their versions:

• editorjs/checklist (1.3.0),
• editorjs/delimiter (1.2.0),
• editorjs/header (2.6.1)
• editorjs/link (2.3.1)
• editorjs/list (1.6.2)
• editorjs/paragraph (2.8.0)
• editorjs/underline (1.0.0)
• editorjs-text-color-plugin (1.1.22)

[MrJuanGaviriaK]

Hi @komaldembla, @juanhurtado10

I've checked the issue and I noticed it is not related to the undo plugin.

Editor.js does not manage a line break as an empty block or an empty paragraph block then, the undo plugin just can't restore it because this is not even persisted into the history stack:

There are workarounds to solve this:

• Use ENTER+SHIFT to lines break, you would get:
• Use editorjs-break-line, If you need a breake-line component, editorjs-undo works perfectly with this plugin

But definitely, a root solution may be done on the editor.js core. Here are some references:

• https://github.com/codex-team/editor.js/issues/1267
• https://github.com/codex-team/editor.js/issues/1387

Best, Juan Gaviria

[komaldembla]

Thanks for the quick response here @MrJuanGaviriaK! I'll check the workarounds.

[juanhurtado10]

@komaldembla @MrJuanGaviriaK

https://user-images.githubusercontent.com/1649973/132592356-07366fb1-227a-42b5-ad22-ae9e48517610.mov

After researching, I found that the following config allows the Undo plugin to recover the empty blocks.

  paragraph: {
    class: Paragraph,
    inlineToolbar: true,
    config: {
      preserveBlank: true,
    },
  },
  ...

[komaldembla]

@juanhurtado10 - Thank you so much! This works :)