Click on a mailto: url renders Revolt unusable

[philn]

STR:

1. click on a mailto: url sent through a Matrix room
2. A popup appears asking to select which email client to use
3. Select either one of the clients proposed

Current behavior: After 3, Revolt loads the mailto: url and displays an error page
Expected behavior: Revolt doesn't try to load the mailto: url since it was previously handled with an external email client