Error: SecurityError: An insecure SockJS connection may not be initiated from a page loaded over HTTPS

In config.json, the details are default. Here is the log.log file contents:

{"message":"Server Error","stack":"Error: listen EADDRINUSE: address already in use :::5000\n    at Server.setupListenHandle [as _listen2] (net.js:1301:14)\n    at listenInCluster (net.js:1349:12)\n    at Server.listen (net.js:1437:7)\n    at listen (/jot-server-1.0.3/node_modules/connected/index.js:47:24)\n    at create (/hjot-server-1.0.3/node_modules/create-server/index.js:166:5)\n    at new createServer (/hjot-server-1.0.3/node_modules/primus/index.js:1118:40)\n    at Object.<anonymous> (/hjot-server-1.0.3/modules/server.js:20:18)\n    at Module._compile (internal/modules/cjs/loader.js:959:30)\n    at Object.Module._extensions..js (internal/modules/cjs/loader.js:995:10)\n    at Module.load (internal/modules/cjs/loader.js:815:32)","code":"EADDRINUSE","errno":"EADDRINUSE","syscall":"listen","address":"::","port":5000,"domain":{"_events":{},"_eventsCount":3,"members":[]},"domainThrown":true,"level":"error","label":"jot-server-1.0.3/app.js","timestamp":"2019-11-25T13:13:27.229Z"}