NOTE: XML contents changes according to the versions. In the future, registry parameter name and the URL itself may change also.
There is a default link to XML for downloading WVD Client which is stored in the following registry parameter:
From this link we can see the versions of WVD Client which are going to be downloaded by the corresponding versions of RAS Client:
For example, we will copy one of the links for WVD Client x64 installer
Then we can paste the link into a browser to see if we can download client:
Or use it for checking the URL response status: