After you have finished the test, please contact Codility Support and explain the issues you experienced. We promise to look into your problem.
As a quick workaround, remember that you can refresh or restart your browser safely, or re-enter the test through the same link. Codility auto-saves whenever you stop typing, so it is highly unlikely that you will lose your code.
If your browser has problems with the Codility interface, it might be caused by the interference of browser extensions or custom settings, so it is a good idea to try another browser from our list of supported browsers: Chrome ≥ 115, ChromiumEdge ≥ 115, Firefox ≥ 115, Opera ≥ 101, Safari ≥ 15.