715280 - Downloadable fonts flash even when the font hasn't expired and no load occurs

Status: RESOLVED WORKSFORME

(Core :: Graphics, defect)

Description

[Joe Drew (not getting mail)]

My site, SaveTransitCity.com, uses a downloadable font, and serves it with Expires: <now + 1 year>. Gecko doesn't even request the file from the server when I click links, but it still takes a significant amount of time before the font displays on those subsequent page loads.

Chrome and Safari, by contrast, display the font immediately.

Comment 1

[Jonathan Kew [:jfkthame]]

We still go through a "load" process to access the fonts, even though they may be cached so that this doesn't result in a request to the server. But on other pages (e.g. try repeatedly reloading http://opentype.info/demo/webfontdemo.html) this doesn't seem to result in a perceptible delay.

I notice (using NSPR_LOG_MODULES=fontdownloader:5) that on your site, we start several load operations for each font, though only one of them completes; the others are abandoned. Could this indicate that something is modifying the page's stylesheet dynamically during the load, in such a way that we repeatedly discard our user font set and build a new one, causing the font loads to be restarted? And if there are a bunch of other resources (css, js, images, etc) being loaded by the time the final font set is ready to kick off its font loads, maybe it gets held up until something else completes and frees up a network channel?

Maybe bz or dbaron would have more insight - I don't really know much about the stylesheet-munging or network/cache/etc stuff that might be involved here, just speculating based on the observed behavior.

Comment 2

[Jonathan Kew [:jfkthame]]

Joe, do you still see this problem? I don't seem to be able to reproduce it with a current build. (One thing that I thought could have helped is bug 816483, but I'm not seeing the issue even with FF18, which predates that fix.)

Comment 3

[Joe Drew (not getting mail)]

I don't think I see this problem any more, no. I could bisect if you were really interested in what changed the behaviour!