Hi,
We are migrating our Web Application from 10.4.1 to 10.7.1 using AGOL. But I do not see any AGOL documentation to migrate webmap and is Web Appbuilder 2.7 compatible to ArcGIS 10.7.1.
I believe the web map itself should be fine during the upgrade. Also, your web app should continue to work like normal as well (I am still running an app on 1.3). When you upgrade ArcGIS Enterprise, it doesn't touch your custom web apps. However, you do have the option to upgrade your web apps, although it might cause any customization (custom widgets, etc.) to no longer work.
Upgrade apps—Web AppBuilder for ArcGIS (Developer Edition) | ArcGIS for Developers
Thanks Ryan, that's helpful.