JetKVM Helper od Andrew Kidd

Adds screenshot and video capture buttons to the JetKVM UI, plus optional URL-triggered keystrokes for scripting.

JetKVM Helper adds two buttons to the JetKVM toolbar and, if you want it, a way to drive the remote machine from a script.

SCREENSHOT
Saves the current frame as a PNG. It captures the video stream at full resolution, so you get the remote machine's actual screen rather than a crop of your browser window. Any brightness, contrast or saturation you've set in JetKVM's video options is applied to the saved image too, so the file matches what you were looking at.

RECORD
Click to start, click again to stop. The clip downloads as a .webm, recorded from the video stream itself - no browser chrome, no window borders, and no separate screen recorder.

SCRIPTED INPUT (off by default)
Turn this on and you can send keystrokes by opening a URL, which means any script or scheduled task can drive the machine. Useful for stepping a server through a BIOS or boot menu unattended and grabbing a screenshot at each stage.

?key=F2
?text=root
?screenshot=bios
?steps=[{"codes":["ArrowDown"],"delay":300},{"codes":["Enter"]}]

The popup shows your command URL, and opening it with no parameters prints the full key reference.

WORKS WITH ANY JETKVM
Local devices sit on whatever address your network gave them, so there's nothing to configure. Point your browser at your JetKVM and the buttons are there.

PRIVACY
Nothing is collected and nothing is sent anywhere. Screenshots and recordings are made in your browser and go straight to your downloads folder, and your settings stay on your machine. The extension runs no server and makes no network requests of its own.

It asks for access to all sites because a JetKVM can be at any address on your network, so there's no fixed domain to request. It stays completely inactive on every page until it recognises a JetKVM.

Source: https://github.com/andrewiankidd/BrowserExtensions/tree/master/jetkvm-helper