How to fix Experience Builder app slow load time

[OliverIshmael]

My Experience Builder app (just a map with all layers switched off and no widgets) can take up to 5 minutes to load first time in Microsoft Edge v121.0.2277.112

When i view the browser Developer Tools Network tab around midday at work the performance of the app is: 2270 requests | 3.1 MB transferred | 77.5 MB resources | Finish 15.1 min | Load 760 ms

At midnight the same app is quicker to load presumably because the server is not as busy , but it still seems slow: 1432 requests | 11.1 mb transferred | 62MB resources |Finish 58.65s | DOM Content Loaded 165 ms | Load 453 ms

When i review the Developer Tools console i can see that it has a lot of errors (see attached log), for instance:

• init.js:108 [esri.tasks.support.Query] 🛑 DEPRECATED - Module: esri.tasks.support.Query
• index.js:113 Create datasource error. {id: 'dataSource_4-3003ff22d73b4aa3b42a9b726fe06e14', dataSourceJson: {…}, layer: w, parentDataSource: c, jimuChildId: '3003ff22d73b4aa3b42a9b726fe06e14', …} TypeError: Cannot read properties of null (reading 'toLowerCase')

Can anyone explain how i solve these?

[Laura]

I don't know much about the dev tool errors but I did also have an issue with things running slowly. Have you restarted portal, server & datastore? What about the server(s) these are hosted on? How many layers & maps are you hosted in Portal. Cleaning this up has helped me immensely. You can also go into server manager and try to change some layers between shared  dedicated instances. Sometimes even clearing browser cache can help.