I have seen that while copying testcases on codechef the whole page below the test case gets selected this specially feels sometimes disturbing during short contests, so I have made an extension to copy all the test cases of the problem which you have opened just by clicking on the extension icon, also it acts as a bookmark when you’re not on codechef.
I have been using it from quite some time and now always feel like using it. I have published it on the webstore do give it a try, only 1Kb in size.
Link : Competitive Companion
Video Overview : Youtube
Do give your suggetions below
Happy coding !!!