If you press e.g. Command+J on macOS, you get press event for both Command and J. But when you release the keys, you only get release events for Command. So J ends up stuck down from the server's perspective. In most cases, this doesn't matter, and it will resolve itself once focus is lost or J is pressed by itself. Still, there are probably cases where it is important. Upstream bug report: https://github.com/novnc/noVNC/issues/1695 Browser bug reports: https://bugzilla.mozilla.org/show_bug.cgi?id=1802465 https://bugs.chromium.org/p/chromium/issues/detail?id=1393524 https://bugs.webkit.org/show_bug.cgi?id=55291 Workaround got added upstream: https://github.com/novnc/noVNC/pull/1698 Unfortunately, it means that applications cannot tell how long the key is pressed down. So it is not ideal.
