Future versions of the Firefox browser will support a feature that will stabilize the browser window and prevent the pages from moving when loaded. This happens when images and ads are uploaded to a higher section of the page and push the content you see down and out of view.
The feature is known as "scroll anchoring" and is rumored to be the work of the World Wide Web Consortium (W3C), the official web specification body.
Changes to the [DOM] data on the page above the visible area of a scroll bar may cause the page to move while the user is in the middle of the "loading" of the content. This feature proposes a mechanism for alleviating this unpleasant user experience by monitoring the position of an anchor node and adjusting the scrolling accordingly.
The first browser that adds support for scroll anchor and the group of developers who started working through the API is Google Chrome. Work on adding scroll anchoring to Chrome started in 2016 in March after users complained about the problem a year earlier, and the feature that was released with Chrome 56 was released in January of 2017.
Opera Software added support a month later with the release of Opera 43, while the Baidu browser followed in April of that year. The Edge, Safari and Internet Explorer have never released support for scroll anchoring.
Now, almost two years after his initial efforts Chrome to stabilize the page load experience, eliminating unnecessary position shifts, the feature is finally added to Firefox.
According to a tweet from Mozilla developers today, the task of adding support for the roll-out anchor in Firefox was finally completed after the initial efforts started in September of 2016.
The current release of Firefox Nightly released today supports the scroll anchor and the feature is expected to be released with the official launch of Firefox 66 in March of 2019.