NoVNC terminal got un-responsive after pressing (Cmd + Shift + 4)

[Ankit8969]

Describe the bug
When I was taking the Screen shot from the novnc window in Mac (1.6 version)
I pressed (Cmd + Shift + 4) , after that novnc window become un-responsive but the same thing was working in older version of novnc(0.6)
We are using IBMi VM Console.

To reproduce
In the NoVNC window try to take the SS.

Expected behavior
Window should not get stuck / hung.

Screenshots
NA

Client (please complete the following information):

• OS: Mac
• Browser: Safari / Chrome
• Browser version: Latest

Server (please complete the following information):

• noVNC version: 1.6
• VNC server: [e.g. QEMU, TigerVNC]
• WebSocket proxy: websockify

Additional context
NA

[CendioOssman]

We have #1799 for this issue, as it is something that's been around forever.

0.6 is an absolutely ancient version of noVNC. No idea why it worked better for you there, but that keyboard code had lots of other issues and this was probably just a lucky side effect.