registerPlugin for the new block editor for widgets?

[davidwebca]

Hi everyone,

I have a small plugin that allows to edit the width of the sidebar in the block editor (https://github.com/davidwebca/wordpress-menu-classes). I currently prevent the enqueueing of the JS code in the new block editor in widgets because it used to crash. Now I realize it doesn't crash, but it doesn't work either. Am I missing something? The 5.8 announcement clearly states that "The Widgets screen is extendable via block editor APIs such as registerPlugin [...]" but it doesn't seem to be the case at all.

Maybe I'm doing something wrong, maybe I'm importing the JS modules from the wrong source, etc. but I can't seem to find any documentation on this specific issue. Any help would be welcome!

Thanks a lot ✌️

[t-hamano]

As far as I know, registerPlugin supports all editor instances, including the widget editor.
However, PluginSidebar and PluginSidebarMoreMenuItem for displaying the UI appear to be unavailable in the widget editor.

// ✅ Works in the post editor
import { PluginSidebarMoreMenuItem } from '@wordpress/edit-post';

// ✅ Works in the site editor
import { PluginSidebarMoreMenuItem } from '@wordpress/edit-site';

// ❌ Doesn't work in the widget editor
import { PluginSidebarMoreMenuItem } from '@wordpress/edit-widgets';

[davidwebca]

Yeah that's what I realize. Shouldn't it be? 🤔

[t-hamano]

In the widget block editor, I could not determine if there is some technical hurdle that prevents the plugin sidebar from being expanded, or if it is planned to be implemented in the future.
It might be a good idea to suggest this in an issue.

[rmorse]

Seconding a need for this, I have a block which has a button in its inspector to open a sidebar, however the block won't work in the classic widgets screen, although it looks like this screen can handle sidebars from a UI perspective.

I think supporting this here would add consistency to the block editor experience.

[t-hamano]

@davidwebca
@rmorse

I would like to create an issue from this discussion to bring to the attention of more people and because I believe this should be treated as an enhancement 👍

[t-hamano]

Created as #47029