Books and other third party widgets dissapeared on Mac

For macOS 12 Monterey where this posting is appearing

Add and customize widgets in Notification Center on Mac

For macOS 14 Sonoma as per user Profile " MacBook Air 13″, macOS 14.0 "

Add and customize widgets on Mac

As for the Widget for the Native application Books

From macOS 14.4.1

I do not see a Native Books Widget

Alphabetical order in below

Spotify widget - do not use Spotify, so can not say if there is or is not such a Widget

Check with the Developer

Sorry but as another Posting has reached the " Best Reply " statues, there really is not too much to add.

If you still feel cheated on the level of support offered

Then have a few suggestions ;

Start now and open an Apple Support Ticket as they are PAID  Apple Employees to deal will these types of issues . 

 Product Feedback - Apple and make it known to Apple regarding this ongoing issue 

One possible reason for this could be a glitch or temporary issue with the macOS system or the apps themselves. Sometimes, widgets may disappear or behave unexpectedly due to software bugs or conflicts.

Here are a few steps you can try to troubleshoot and potentially resolve the issue:

Firstly, try restarting your MacBook Air. Sometimes, a simple restart can resolve minor software glitches or inconsistencies. Check if the widgets reappear in the notification center afterward.

Ensure that your MacBook Air is running the latest version of macOS available. Apple often releases software updates that include bug fixes and improvements, which could address issues with widgets disappearing.

If the widgets continue to be missing after restarting and updating macOS, consider reinstalling the Books and Spotify apps from the Mac App Store. This may help refresh the app's settings and restore the widgets.

Another step you can try is to reset the notification center preferences on your Mac. Open the Terminal app and enter the following command: `defaults delete com.apple.notificationcenterui`. After running this command, restart your Mac and check if the widgets reappear.

If none of the above steps resolve the issue, it's possible that there may be a more specific issue with the Books or Spotify app. In this case, you can reach out to the respective app's support team for further assistance. They may be able to provide guidance or troubleshooting steps tailored to their app's functionality.

If the issue persists despite trying these steps, you may also consider seeking assistance from Official Apple Support or visiting an Apple Store for further diagnosis and support. They can help investigate the issue in more detail and provide personalized assistance based on your specific situation.

Be very careful using the Terminal Command line

It is very unforgiving

One wrong period or back slash in the wrong place can have very serious consequences

If not familiar with Terminal Command Line and the usages of it, do not use it