Annoying banner: "Looks like you're trying to copy to the pasteboard..."

Thanks for filing an issue! Please answer the questions below so I can help you.

• iTerm2 version: Build 3.3.10beta4
• OS version: Mac OS 10.14
• Attach com.googlecode.iterm2.plist here (drag-drop from finder into this window)
• Attach a debug log, if possible. Instructions at https://iterm2.com/debuglog
• Are you reporting a performance issue, excessive CPU usage, or a hang? Please attach a sample. Instructions at HowToSample
• Are you reporting a crash? Please attach the crash log. Instructions at crash logs
• Are you reporting excessive memory usage? Please attach a heap analysis: heapshot

Detailed steps to reproduce the problem:

1. Open iterm
2. Create a tmux session (run tmux)
3. Using the mouse, select a bit of text on the terminal an copy it using CMD+C

What happened:

A banner appears on the top of iterm

Notice that there is no option to prevent the banner from appearing again after it is dismissed.

What should have happened:

The banner should not have appeared, or it should have contained an option to prevent it from being shown again.

I have tried to locate any global iterm config option to disable this behaviour on the documentation and interface without luck.