What is the platform default width

NOTE: This help page only applies to Firefox users.

The Platform default width is the width that Firefox automatically uses for your operating system. Depending on your operating system, this can sometimes be adjusted in your operating system settings.

For more information on enabling wide scrollbars in Firefox, please refer to How to enable wide scrollbars on Firefox.

Why is there no custom width option on Firefox?

Firefox is currently using the draft W3C CSS Scrollbars Module Level 1 standard. This standard does not provide the ability to use any width other than the 3 presets defined in the standard (auto, thin and none).

The W3C standard rejects the approach taken in the WebKit implementation (used by Google Chrome and Microsoft Edge), citing issues such as inconsistent scrollbar structures on other operating systems. The W3C has described that level of customization as "not a good idea" and "a feature mistakenly exposed to the web".

What have I done to try and change this?

Unfortunately, I am only able to offer functionality that is supported by the Firefox browser. In this case, the functionality is being dictated by W3C. I have made attempts to have improved scrollbar width customization added to the standard that's being used, with no success.

On May 2 2021, I made a request to have custom widths added to the standard. The request was rejected, saying "...multiple browser implementors objected to allowing arbitrary sizes, as it would interfere with usage of the browser-default scrollbars."

On June 4 2021, I made a request to have a "wide" option added to the standard. I expressed my concern over accessibility issues for users with specific accessibility needs (such as visual impairment), as well as the obvious visual benefits associated with allowing website authors to provide a wider scrollbar. I specifically included the fact that Mac and Linux computers have a scrollbar that has little differentiation from the "thin" option currently supported by the standard.

On July 29 2021, my request was rejected during a W3C meeting, citing that there is a lack of "identified use case" and saying they "don't usually add features without a known use-case".

On October 20 2021, my request was discussed during a CSS & APA annual meeting, where the concerns over accessibility were the primary focus. While the discussion has resulted notations and warnings being added to CSS Scrollbars Styling Module Level 1, further discussion about the scrollbars was deferred to another meeting later in the year.

On November 10 2021, the Accessible Platform Architectures Working Group Teleconference discussed the accessibility issues surrounding the scrollbar widths. Ultimately, the group felt that the changes to the scrollbar specification were sufficient and there was no reason to add a "wide" width option.

Finally, on January 13 2022, my request to add a "wide" option to the specification was locked by the W3C after another concerned user attempted to provide a valid use-case for the change. They included a quote from the W3C's own Making Content Usable for People with Cognitive and Learning Disabilities document to highlight that the lack of a "wide" option goes against W3C's own accessibility objectives and could be potentially harmful for people with disabilities. Locking the discussion now prevents further discourse on the topic, virtually ensuring that the option will never be added.

What's next in the fight for change?

Sadly, the W3C is unwilling to pivot from their current opinion on the matter. Comments such as "...we don't think that allowing web pages to deviate from the system norms is useful" have been echoed by a variety of people involved in the decision making process at W3C in each of the requests made for expansion of the standard over many years, showing they are unwilling to change their mind.

The only remaining option is to request that Firefox offer support for this functionality. This would require Firefox to deviate from the W3C specification, which is an unlikely outcome.