Which Umbraco version are you using?
17.0.2
Bug summary
The slider is broken when range is not enabled. You get an error that a value has been set, but that a range was not expected:
I initially assumed the built-in property value preset was at fault, but the issue seems to lie deeper than that.
Specifics
No response
Steps to reproduce
Create a slider data type. Range should not be enabled. It should have an initial value set.
Use this data type on a content type and create some content using this type.
You are unable to publish until you manually change the value.
Expected result / actual result
No response