Is it possible to open the operating system file explorer/browser to allow users to select a directory instead of just files, without using the webkitdirectory attribute of an html input tag? It appears that the Dropbox website does this for folder uploads, but perhaps they add the webkitdirectory attribute programatically. (I'd rather not use the webkitdirectory attribute because it is non-standard, not recommended for production, and my Svelte app is complaining about it).
As noted by @Mark Hanna, I used the File System Access API instead of the webKitdirectory input attribute. In TypeScript, the methods of the API were not recognized, so installed the @types/wicg-file-system-access and in the .tsconfig added
"compilerOptions": {
"types": ["@types/wicg-file-system-access"]
}