Try Gutenberg Callout: broken UI when clicking multiple times on Install Classic Editor

[mathieuhays]

Steps to reproduce:

1. Click on "Install Classic Editor"
2. Button changes to "Installing..."
3. Click again on the button (nothing visual happens at that point, still installing)
4. Button changes to "Activate Classic Editor" with the progress icon (rotating arrows) still showing. An error message is also displayed mentioning the directory already exist.

How to fix:

Prevent the button callback to send another install request if it's already installing.

[mathieuhays]

Try Gutenberg Callout: Broken UI

[ianbelanger]

I can confirm that this issue exists. Screenshot coming

[ianbelanger]

Try Gutenberg Install Classic Editor error

[subrataemfluence]

A possible solution could be if we can make the button non-clickable further during the installation is in progress like @mathieuhays suggested.

Prevent the button callback to send another install request if it's already installing.

The problem this is not a button, a hyperlink instead. So we cannot use conventional disable attribute here.

Using CSS3 property pointer-events: none along with a cursor: default; had worked for me in both Chrome and Firefox.

File: /wp-admin/js/updates.js

wp.updates.installPlugin = function( args ) {
   [...]
   if( 'dashboard' === pagenow && 'classic-editor' === args.slug ) {
      $message.attr( 'style', 'pointer-events: none; cursor: default;' );
   }
   [...]
}

[garrett-eclipse]

As the Try Gutenberg Callout was deprecated in WP5.0 I'm going to close this as no longer applicable.
Changeset - https://core.trac.wordpress.org/changeset/44106