1897490 - demos.telerik.com/kendo-ui/m/index relies on prefixed transitions (which were removed to avoid issues with CSS zoom)

Status: NEW

(Web Compatibility :: Site Reports, defect, P2)

Description

[github.com]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:126.0) Gecko/20100101 Firefox/126.0

Steps to reproduce:

Using KendoUI by Telerik. They appear to be probing the HTMLElement.styles class to determine what capabilities the browser supports. Specifically they do (in JavaScript, of course):

const el = document.createElement('table');

if (typeof el.style.MozTransition === 'string') { ... }

That specific JS property disappeared between Firefox 125.0.3 and 126.

Actual results:

https://demos.telerik.com/kendo-ui/m/index#actionsheet/index

• renders a blank page in Firefox 126. It works in Firefox 125.

Expected results:

No regression.

To confirm the regression, simply open up the Firefox JS inspector and run:

var el = document.createElement('table');
typeof el.style.MozTransition 

In Firefox 126, the property is undefined. In Firefox 125 it is a string.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::CSS Parsing and Computation' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Emilio Cobos Álvarez (:emilio)]

This was intentional and needed to prevent issues with zoom and -moz-transform, see bug 1861730 and related bugs.

In general, I don't think we want to bring them back (this can be done via layout.css.prefixes.transitions in about:config), so the best path forward is probably contacting them.

I contacted them in https://www.telerik.com/contact?preselect=kendo-ui, but if someone has a more direct contact it'd be great.