Andrea Porotti

Using this plugin you can attach notes to some elements in the WordPress dashboard, such as:
<ul>
<li>posts</li>
<li>pages</li>
<li>custom post types from other plugins (except the notes from this plugin)</li>
<li>users</li>
<li>plugins</li>
<li>dashboard sections</li>
<li>the whole dashboard</li>
</ul>
It can be helpfull if you manage a site with other people or just to take notes for yourself.
Features
<ul>
<li>manage notes like the standard posts by opening the Notes page from the admin menu.</li>
<li>while editing a note, use the meta box on the right to set note properties (position, color,…)</li>
<li>manage section and global notes from the admin bar.</li>
<li>manage item notes (eg. posts and pages) from the custom column in the admin pages.</li>
<li>get notes details by hovering the mouse on the “Info” links or clicking on the “I” icons.</li>
<li>add text, images and links in the note content.</li>
<li>deleted notes go to the trash, so they can be restored.</li>
<li>automatically discovers custom post types added by other plugins (eg. events, books…).</li>
<li>creates a list of the dashboard sections based on the admin menu items.</li>
</ul>
Configuration
Settings for the plugin are available on the Settings -> JAMP Notes page.
Please note:
<ul>
<li>by default the plugin data is kept after uninstall. You can choose to delete notes and settings enabling the data removal option.</li>
<li>after activation, the plugin enables notes for all the existing public post types. If you then install other plugins which create new post types, you have to manually enable them in the JAMP settings.</li>
</ul>
Permissions
The notes are currently available only for the users with the “Administrator” role. 
Each Administrator can manage all notes.
Support
If you find any errors or compatibility issues with other plugins, please let me know in the support forum. Thanks!
Privacy
This plugin does not collect or store any user data. It does not set any cookies and it does not connect to any third-party services.

JAMP Notes (Just Another Memo Plugin)

This plugin allows you to attach notes to some WordPress elements like posts, pages, dashboard sections and more.

wpgear

This Plugin allows you to Add personal Notes, comments, memo to each of the Plugins. 
You can change or delete any Note at any time. 
Notes are available to anyone who has access to the Plugins page.
Here are some reasons why “Plugin Notes Label” is needed and useful: 
– Over time, sometimes you forget exactly why this or that Plugin was installed. 
– Some Plugins have to be modified (although this is not correct), and their updating requires special attention. That is, you need to remind yourself and others that you cannot update such a Plugin without careful preparation. 
– Sometimes you expect a specific new promised functionality from a certain Plugin, and up to this point, all intermediate updates are not particularly important. 
– Anyone who administers WordPress can remember a few more similar reasons. ))
<h4>Features</h4>
<ul>
<li>Add, Edit, Delete Notes – does not require page refresh.</li>
<li>Notes fit neatly and compactly into the general list of Plugins without breaking the original style.</li>
<li>Displays Notes on the page: “update-core”. This is especially important if any Plugin requires special attention.</li>
<li>Works correctly with Translated Plugin Names.</li>
<li>Works correctly with HTML Entity in Plugin Names.</li>
<li>Setup-Page:
<ul>
<li>“Enable Setup-Page for Admin only” On/Off</li>
<li>“Show note Author” On/Off</li>
<li>“Show note Date” On/Off</li>
</ul>
</li>
<li>“Import” – “Export”:
<ul>
<li>“Import”. All Notes are imported, along with information about the creation date and author name.</li>
<li>“Export”. If the Note already exists, but it does not exist in the Export file, then the Note remains unchanged. If the File contains a Note about a Plugin that is not on this site, then the Note will be saved and will be displayed when such a Plugin is installed.</li>
</ul>
</li>
<li>“Clear All Notes”:
<ul>
<li>It can be useful in some cases when you need to completely Delete all Notes.</li>
</ul>
</li>
</ul>

JAMP Notes (Just Another Memo Plugin) vs Plugin Notes Label