Be aware of the behavior that the error occurs when using [Save view] in Document Libraries.
In the classic UI, the error occurs when clicking "Save view" to save the view as Personal View after the process of sorting in ascend descending order and filtering the items.
*Error message: "An error occurred while saving the view."
I have confirmed that this problem does not occur in the modern UI, therefore, I hope the feature will be implemented to save the view via [Save view] in the classic UI as well. If this function is not implemented in the modern UI as well. If this function is not implemented in the modern UI, please disable displaying the [Save view] button or make it functioning.