How to delete New Document templates from 'Your Recent Items' in Photoshop?

[fantastic_wanderlust157F]

During Support trouble shooting they created a bunch of New Document templates. They are cluttering my interface and slowing down production. 

How can the New Document templates in the 'Your Recent Items' be deleted in Photoshop?

Support told me the only way is to delete all of my preferences and/or uninstall/re-install PS. There must be a better way. 

[Stephen_A_Marsh]

The path to the MRU New Doc Sizes.json file is user account related and Photoshop version specific and similar to the following...

MAC:

/Users/<user>/Library/Preferences/Adobe Photoshop 2021 Settings/MRU New Doc Sizes.json

Win:

C:\Users\<user>\AppData\Roaming\Adobe\Adobe Photoshop 2021\Adobe Photoshop 2021 Settings\MRU New Doc Sizes.json

You can open the .json file in any plain text editor, however, an editor used for code editing which offers syntax highlighting and formatting for JavaScript is helpful when editing the file to remove unwanted entries. Make a backup before editing just in case you make a mistake with the JSON syntax.