Should I just download the file from https://jqueryui.com/ and replace
it with the same file that is currently in the jquery-ui folder?
Yes, it is also a quick way to update the client-side libraries. Another way, you can use Libman in visual studio to update the client side library version.
For both of the two ways you can choose to update the client-site libraries.
For which way to choose, you need consider:
If you download the jQuery ui by official website before, using libman contains a disadvantage that you may need update references in views. Because the folder download by the two ways may different.e.g. The jquery-ui.css contains in the root folder if downloading by website, but it contains in rootfolder\themes\base\jquery-ui.css if downloading by libman.
For how to use Libman, detailed steps you could follow
- If your project already uses LibMan, you will find a
libman.json file in the root of your project. Open this file.
- If your project does not have a libman.json file, you can add one by right-clicking on the project in Solution Explorer, then selecting Manage Client-Side Libraries.
Configure libman.json:
{
"version": "1.0",
"defaultProvider": "cdnjs",
"libraries": [
{
"library": "[email protected]", // specify the latest version here
"destination": "wwwroot/lib/jquery-ui-1.13.2/", //the location of the jquery ui
"files": [
"jquery-ui.min.js", //the file you want to update
"jquery-ui.js"
]
}
]
}
The libman.json contains the intelliSense when writing the files you want to update, so you don't worry about making mistake.

But if you need update multiple or whole referenced files and do not want to manually wirte the json.
You can firstly delete all the file in your current jquery-ui root folder and maintain the root folder of jquery-ui(jquery-ui-1.13.2 here in my project).
Then right-click on the project in Solution Explorer, select Add > Client-Side Library. Choose the package and location you want like below.

At last click the Install button, it will download all the referenced file in this folder.