Also, embeds displayed in XFMG are kept to their original dimensions unless they're exactly 640 ✕ 360.
New uploads are embedded via a native HTML5 player.
Old uploads still use the Flash player. Vocaroo doesn't seem to have an upgrade path for those.
You don't need to upgrade if you don't use a proxy for outbound requests.
An option has been added to remove the limits on the dimensions of regular embeds such as YouTube's. Instead of being limited to 640 × 360 pixels, they will occupy as much screen space as possible. This does not apply to dynamically-sized embeds such as tweets and embeds with a custom aspect ratio.
The option is disabled by default.
Also removed defunct site Tinypic.
Mixer supports embedding live streams and VODs but not clips.