How can I change "rbxthumb://" to an actual external image

I want to post a headshot of a players avatar (using webhooks) in discord every time they join the game. The thing is though it comes out with rbxthumb:// instead of an actual image. I used the following line of code to get this: Players:GetUserThumbnailAsync(UserID, ThumbnailType, ThumbnailSize)

The variables are pretty self explanatory. I just want to know how to turn that into a real external image.
Could be via link.

Try this and let me know if it works!

It should, but there is a possibility it may not. Not too familiar with webhooks, but it should be just fine.

local function getThumbnail(plr: Player, thumbnailType: Enum.ThumbnailType, thumbnailSize: Enum.ThumbnailSize)
	return Players:GetUserThumbnailAsync(plr.UserId, thumbnailType, thumbnailSize)

local success, content, ready = pcall(function()
	return getThumbnail(player, Enum.ThumbnailType.HeadShot, Enum.ThumbnailSize.Size420x420)

--// Send "content" thru the webhook page lists a number of endpoints you can send requests to (specifically the Avatar section in your use case) that will return a reply with a content URL. You will need to use a proxy to make requests to these endpoints from in-game, however.