How to add higher quality thumbnail for Facebook video?
Go to your video on Facebook.
Select the "Video options" button.

On the pop-up, go to the "Change thumbnail".
Click the "Upload Image" button to upload a higher-quality thumbnail image.

Click the Save button.
Select the "Video options" button.

On the pop-up, go to the "Change thumbnail".
Click the "Upload Image" button to upload a higher-quality thumbnail image.

Click the Save button.
Updated on: 11/29/2023
Thank you!