What WebRTC is
WebRTC is the browser's real-time communication stack. The W3C specification defines the JavaScript APIs, which work with a set of IETF protocols summarised in RFC 8825, to send audio, video and arbitrary data between browsers and devices. Connections are negotiated with ICE, which uses STUN to find direct paths and TURN to relay when they fail, and media is always encrypted.
How a WebRTC remote desktop works
In a WebRTC remote desktop, the remote computer captures its screen and sends it as a real-time video track, while keyboard and mouse input travel back over a data channel. The operator only needs a browser, which is the model's big advantage.
The trade-offs come from the same design: video is limited to the codecs the browser supports for WebRTC, and on restrictive networks everything depends on a TURN relay being reachable.
Vexaro Desk's browser viewer
On the Team plan and above, Vexaro Desk offers a browser viewer in the Vexaro console, and it does not use WebRTC. The operator opens it in a browser, with nothing to install, and sees and controls the remote Windows computer, with input and clipboard sent back from the browser.
A browser session passes through a Vexaro server that bridges the browser to the remote computer. Every leg is encrypted, but that server decrypts the stream in between, so a browser session is not end-to-end encrypted. The remote computer runs the Windows client either way.
When to use which
Use the browser viewer when you cannot install anything on the computer in front of you. Use the Windows client when you want a direct, end-to-end encrypted session and the full set of controls, such as quality presets and switching between monitors.