Make "Mark diffs in protocol" accessible to color blind users

[aurelf]

Is your feature request related to a problem?

The "Mark diffs in protocol" feature is a nice way to highlight differences between packets, but current color choice isn't suitable for color-blind users.

Describe the solution you'd like

An easy way to address this would be to make the font used to highlight the differences in red but also bold font.

Describe alternatives you've considered

Another option would be to use specific colors (accessible palettes) could help:
https://davidmathlogic.com/colorblind/#%23D81B60-%231E88E5-%23FFC107-%23004D40

Other comments

I'm not sure about the other colors used in other parts of URH (the diff showed up in a lab with students, we didn't really use the other features using color coding).

[andynoack]

Actually the diffs are already indicated using red AND bold font, just approved with Linux. Maybe your operating system changes that somehow?

[aurelf]

I checked and indeed the font is already bold. I didn't notice before, and it seems that the student didn't see the difference, so it seems that bold wasn't visible enough...