Dear XQuartz developers, I have a class where the majority of students are using Macs and XQuartz to interact with an app running on Linux. They are developing code with the app, so are doing a lot of copying and pasting. The students are used to using Cmd-C and Cmd-V to copy and paste, but the app expects Ctrl-C and Ctrl-V. Googling how to map the keys led to your website, where I tried the solution offered at https://xquartz.macosforge.org/trac/ticket/398 which is to have the students use this .Xmodmap file clear mod2 clear control keycode 63 = Control_L keycode 67 = Control_L keycode 71 = Control_L add control = Control_L Unfortunately, this doesn't work. I'm sure this is a commonly desired functionality and there must be a solution. Could you please tell me how to accomplish this key mapping. These are our XQuartz Pasteboard settings: Enable syncing: y Update Pasteboard when CLIPBOARD changes: n Update CLIPBOARD when Pasteboard changes: y Update PRIMARY (middle-click) when Pasteboard changes: y Update Pasteboard immediately when new text is selected: n Many thanks, Bill