@WebStormIDE Actually it might be a Node.JS file. The file I can't set breakpoints in is "timers.js". I tried unchecking "Do not step into library scripts" in the Debugger Settings, but I still can't trace that file.
Can you please provide a bit more detailed description for the problem in a new issue on https://youtrack.jetbrains.com/issues/WEB Please share a link to the project, paths to the files where you try to put the breakpoints, screenshots showing these files...