Since I cannot search for this with meaningful results, I can't be sure that this is not a duplicate.
However, I am running a JSSOR Slider on my site and some of the elements have a u property for example:
<div u="slides" style="cursor: move; position: absolute; left: 0px; top: 0px; width: 1300px; height: 500px; overflow: hidden;">
This "u=slides" is throwing up an error when I run it through a W3 Validator, however when I remove this property from the element, the slider no longer functions.
I am wondering the purpose of this property as I see no markup for it anywhere, and wondering if it can be substituted for anything in order to make the site pass markup validation.
Thanks in advance.
Custom attributes (in HTML5) can be assigned to elements using the
data-* attribute rather than an invalid attribute named "u", you will not be able to modify this attribute without breaking the way your site functions.
Update: Digging deeper I've discovered that this was already raised as an issue on JSSOR's GitHub repository back in January: https://github.com/jssor/jquery-slider/issues/4. They've rectified this by allowing you to use a valid
data-u attribute instead of
Provided your JSSOR plugin code is up to date. You can simply modify your HTML to:
<div data-u="slides" style="...">
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