I have encountered the following error when scrolling to the bottom of one of my forms:
Initially I thought it was an issue with the library control I had on the page as that is why I was troubleshooting to begin with. I deleted the control and this error still comes up.
I can interact with the form without issue until I scroll to the bottom.
This is a known issue related to a recent SharePoint update. You need to update your app package and re-save the forms with the latest version of Forms Designer.
We usually send out a newsletter whenever you need to upgrade the app package.
On top of that, you can always check the latest version here: Plumsail Forms