That's for competitive programming, you really want to stick with the most common tools there. Otherwise you have to learn different set of stuff for each on-site competition. Common as in "included in the standard OS image at competitions".
For example, I use Far Manager/Kate for competitive programming and small scripts (sometimes Vim), but not way I use any of these for professional development.
Trying to understand this--are Far Manager & Kate included in the standard OS image at competitions, but your favorite work IDE is not? Or is it more that your work config files & plugins are not available/needed in competitions?
Yes. In some competitions about ten years ago in ex-USSR it was typically Windows + Far Manager (maybe some other stuff, but not always), in international competitions it was some flavor of Linux with a stock KDE (hence Kate) or GNOME (hence Gedit).
No professional IDEs almost certainly (no license to use), and the set of free IDEs depends on what organizers like: some installed NetBeans, some installed Eclipse CDT, some did both, some did neither.
No external resources like configs and plugins are typically allowed either.
Of course, it depends on a competition. I'm mostly talking about IOI (International Olympiad in Informatics for school students) and ICPC (International Collegiate Programming Contest). Online competitions are another beast.
For example, I use Far Manager/Kate for competitive programming and small scripts (sometimes Vim), but not way I use any of these for professional development.