Confusing UX when links are opened in Element desktop

**Describe the bug**
I had a very hard time figuring out how matrix.to was supposed to interact with the Element Desktop client.

**To Reproduce**
1. Go to any matrix.to URL
2. Click on "Continue" (under "Element")

**Expected behavior**
Something like this:

Notice how it clearly points out that it "beamed" the invite link to the desktop app, and explicitly asks me if I want to use the browser instead as an *alternative*.

**Actual behavior**

Nowhere on the page did it say that it already (**silently!**) sent the link to my Element desktop client (via the `element:` protocol handler). If Element is minimized or on a different workspace, there's zero indication that it received any invite links, so unless you have the foresight to manually check the Element client it's easy to miss the fact that the `element:` handler already got invoked. In particular, nothing about this page gave me the impression that it had already sent the info to the Element client.

(Even worse, for this specific link (which was for a group), the link did not actually do anything in Element, presumably due to me having opted into the spaces beta, so even when I manually checked Element to see if it had received anything, nothing was different!)

As a result of this bug, and the very misleading wording of the site, I'm presented with the (wrong) impression that I still needed an *extra* step to actually open the link. In fact, given the *presence* of the "Download for Linux" button, I had thought the issue was that it didn't recognize that I already had Element installed - otherwise, why would it be asking me to download Element?

If I had to rewrite this dialog from scratch, it would read something like:

> ## Success
> \ was forwarded to the Element Desktop client. You can now close this tab.
> ### Not working?
> * Download for Linux
> * Open in your browser instead

(And I would make the "Download for Linux" button white, not blue, otherwise it gives the misleading impression that this is the button I'm *supposed* to click, when the reality is that what I'm *supposed* to do is close the tab)

Start by tracing the matrix.to URL flow after clicking "Continue" under "Element", including the element: protocol handler invocation. Update the page so it clearly confirms when the link was forwarded, explains that the tab can be closed, and presents browser use or downloading Element as alternatives.

Written by the indexing model from the issue text.