I have created a sequence to fill the web form. In normal window i was able to fill the data in web form, but in Incognito mode i was not able to fill the data.
You could try Chrome> More tools> Extensions> UiPath Extension Details> Allow in incognito. Make sure you have checked developer mode in Extensions Panel.
Actually the problem is if you try to do web automation you should enable the extension of uipath, but in incognito so you can enable the developer mode. How you can automate particular work is you should tick the Private in the Properties of Open Browser.