Actually on my side, Codeforces auto-saves the language. Did you enable the cookies or storage or some sort of thing like that?

Hi! Did you manage to find a way to fix your default language? I'm having the same problem where I'm trying to set my default language to GNU G++ 6.4.1, but my default language changes to MS Visual C++ 2010 after about half a day.

I've tried the following, which all failed: 1. Clearing all history on Chrome 2. Disabling adblock on Codeforces 3. Changing my password to disable all other sessions. 4. Submitting in G++14 in Practice Mode, Virtual Contest Mode, and Gym. 5. Using Incognito mode in Chrome

I'm worried that my default language may change in the middle of a rated round. MS C++ and G++ are similar enough that my submission may pass on Test 1, but TLE on system tests.

I also have noticed the same problem recently. I have never submitted a solution in Java at CF, but somehow my default submission language is set to Java. I tried changing it in various ways but couldn't. It's not that annoying, but I would prefer my default language to be set to C++. I'm not sure if it's a bug but still — MikeMirzayanov.

UPDATE: It's still not fixed as of 12.03.2018

if anyone still has the problem. check this