On 2019-03-06 14:29, Lewis Butler wrote:

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Where does the code that prints the email to the window pane exist ?

In your browser and in your Operating System. For example, on macOS I have a preset called “Black and white” which ignores any color in the job and just prints it as straight black and white. Or I can save as a PDF print, then export with a Quartz filter to convert to B&W (or Greyscakle if I prefer)

Here’s an example of that:

https://www.dropbox.com/s/pf00h1nkzepror6/Screenshot%202019-03-06%2007.26.59.png?dl=0

Roundcube creates a “print” window, It doesn’t actually print, that’s up to your hardware.

Ok found it in browser preferences