Mozilla Designer Touts Tricks to Give Firefox the Illusion of Speed

An interface designer interning at Mozilla has suggested that the company mimic gimmicks in Google's Chrome to make users think Firefox starts up faster.

In an entry on his personal blog that was reposted to Mozilla's uber-blog, Planet Mozilla, John Wayne Hill, an Indiana University masters student interning this summer at the open-source company, spelled out changes that would give users the feeling that Firefox starts quicker.

"Firefox is fast, no doubt about it. But for many people it feels pretty slow when starting up," said Hill, who is studying human-computer interaction and design. "Chrome, while only marginally faster than Firefox at starting, feels much faster. By analyzing videos of these start-up processes we can start to understand what makes Firefox feel slow."

Along with Alex Faaborg, a Firefox principal designer, Hill put Firefox and Chrome through speed trials that showed Google's browser finished most start-up tasks milliseconds faster than Firefox, in some cases because the former skipped steps. Hill then compared how both browsers handled specific start-up tasks or informed users of start-up progress.

For example, while Chrome simultaneously draws both the browser window and its "chrome," or interface, before rendering the opening Web site, Firefox does each of the three tasks separately and sequentially. "Chrome seems to do everything at once [which] allows Chrome to feel fast because once the window is [drawn], everything is pretty much ready to go," Hill said.

Google's browser also uses a smaller page loading indicator -- the animated circle at the left side of each Chrome tab -- while Firefox splashes the word "Loading" across the entire tab.

"This is visually 'bloated' and makes Firefox seem slower," Hill said. "Furthermore, because Chrome's loading icon animation goes 'around' faster, Firefox's loading icon takes more time (seemingly) to get 'around.'"

Other pluses for Chrome include its practice of displaying the page title only when the site has been drawn, whereas Firefox fills in the title as a page renders. "This is a simple trick that allows Chrome to feel faster in that once the title is shown, the page is ready," Hill pointed out. "In Firefox, a page's title makes it seem like a page has loaded but in fact the page isn't ready to be interacted with quite yet and [so] the user has to 'wait longer.'"

To better compete with Chrome on perceived startup speed, Hill recommended that Firefox copy some of Google's tricks, including drawing the browser window and chrome at the same time, not sequentially; reduce the "visual weight" of the page loading icon and animate it faster; and delay displaying the page's title until the site has loaded and can be used.

He also suggested that Mozilla update Firefox when the user closes the browser, not when it's first opened, as is currently the case.

"With just a few changes in the Firefox start-up process, we could greatly enhance the feeling of Firefox's speed," Hill argued.

Mozilla has already devoted resources to reducing Firefox's actual startup time, as opposed to Hill's suggestions to give users the illusion of speed. The startup team publishes gains-losses metrics weekly on the Mozilla site, and blogs about its progress almost as frequently.

Firefox has long been bashed as sluggish compared to Chrome and other rivals, with various benchmarks used to illustrate Firefox's lethargy. (In fact, the Mozilla-maintained "Are We Fast Yet" site that monitors the progress of its work on boosting Firefox's JavaScript speeds shows Chrome and Safari far faster.)


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