Sorry, this site can't be saved as a template. It contains apps that don't work in templates: Modern Script Editor web part by Puzzlepart

I am working on a sharepoint online classic team sub-site, and i added this "sp-dev-fx-webparts" from https://github.com/SharePoint/sp-dev-fx-webparts/tree/master/samples/react-script-editor to allow me to add custom scripts inside modern pages. so i went to the subsite's site content link >> i add the web part app, as follow:-

After that i reference the web part inside the sub-site's home page, and i added a javascript inside it. then i tried to save the sub-site as template but i got this error:-

Sorry, something went wrong
Sorry, this site can't be saved as a template. It contains apps that don't work in templates: 
Modern Script Editor web part by Puzzlepart

as follow:-

so my question is; if there is a way to add the web part to my sub-site and be able to save the sub-site as template?

Thanks