UUI Slider performance issue when step has decimal values (e.g. 0.1)

[AleksandrRiabov]

Which exact UI Library version are you using? For example: 1.0.1 - don't just write v1.

UUI bundled with Umbraco CMS v17.3.0 (exact version not directly exposed)

Bug summary

Backoffice slider (uui-slider used in data types) becomes very slow or unresponsive when configured with decimal step values (e.g. 0.1).

• On a clean Umbraco installation, the issue is less noticeable with a small number of sliders

• In a real-world scenario (e.g. ~20+ sliders on a single content page), performance degradation becomes significant

• The issue appears to scale with the number of slider instances on the page

• Using integer step values (e.g. 1) works as expected

• Issue occurs when step contains decimal values (1.0, 0.1, 0.001, etc.)

• Also impacts overall backoffice performance — other property editors (e.g. RTE, Image Picker) load slower when such sliders are present

Specifics

• Umbraco CMS: v17.3.0 (latest at time of writing)
• UUI: bundled with Umbraco backoffice (exact version not exposed)
• Browser: Chrome (also reproducible in other browsers)

Steps to reproduce

1. Create or edit a Data Type using Slider
2. Set:
   • Min: 0
   • Max: 100
   • Step: 0.01
3. Apply this Data Type to a property on a document type
4. Open a content item using this property

Expected result / actual result

Expected result
Content page loads normally and slider is responsive.

Actual result
Content page becomes very slow to load or unresponsive. Slider interaction is laggy.
Other properties on the same page (e.g. RTE, Image Picker) also load significantly slower when a slider with decimal step is present.