We are investigating what seems to be a Firefox bug relating to avatars being cached on disk and then retrieved by a later request. Reported to Firefox as: 1899184 - Firefox is sometimes unable to load/render previously cached images ASSIGNED (jeremy) in GeckoView - General. Last updated 2026-02-23. The way this problem manifests is missing avatars where one would normally be present, e.g.: [image] These are respectively: and those URLs redirect to, respectively: https://europe1.discourse-cdn.com/arduino/optimized/4X/3/3/7/337a5e4169461364c9805cfad882c9eb0332bdf3_2_48x48.png https://europe1.discourse-cdn.com/arduino/optimized/4X/4/b/8/4b8c803f304aa7e7c487184224ec9f970c96e8c4_2_48x48.jpeg While inspecting the DOM using the devtools, Firefox reports “Could not load the image” [image] [image] It’s never on initial requests that this fails - it’s always only happened on subsequent requests that would load the image from cache: [image] Reloading the page sometimes triggers Firefox to load the image properly, e.g.: [image] after a reload: [image] We know that: … the problem is not specific to the Discourse application itself. We have reproduced the problem with a static HTML page containing only links to avatars: [image] [image] … disabling http3 in Firefox does not resolve the problem … flushing the browser cache causes the images to properly load the next time … end users have reported this problem on desktop and mobile We suspect that: … this has something to do with the image being loaded after a redirect Certain of our hosting environments have a “redirect chaser” installed that causes a request to the the original URL to return the image itself instead of a redirect to the image. I do not believe anyone has experienced this problem in those environments. We do not have: a start-to-finish consistent & clear reproduction of the problem

Interesting. OK, if you have any further details or reproduction steps, feel free to post them here. [image] piffy: my site uses bunny.net as a cdn :face_with_raised_eyebrow: :microscope: [The image shows an adorable fluffy bunny with droopy ears and distinctive dark fur patches on its face, sitting on a carpeted floor. (Captioned by AI)] Well, that is EXCEEDINGLY appropriate :laughing:

[image] Michael Brown: loading="lazy" This to me feels like our next port of call @david , a site setting that disables this to see if it has any impact.

Since @supermathie has a vague repro on a static page, perhaps we try creating a version of that without loading="lazy"? Much easier than modifying Discourse to do it. Is that something you could try @supermathie?

I wouldn’t use any other CDN! :rabbit2:

I’ve been reloading them off and on, and just now replicated the problem by loading the lazy page (worked) then the non-lazy page (failed): [image] Unfortunately, Firefox seemed to completely reload assets on reload (Disable Cache is not set) with devtools open, but… this is odd: [image] The user seems to have changed/updated their avatar, and we redirected to the new one? I’m not sure what triggers this @david. I’d hazard a guess this additional redirect briefly triggered the Firefox bug. Which is in line with the difference in behaviour due to the redirect chaser. Maybe I can trigger it? I changed my avatar, let’s see if it breaks when I reload in an hour. EDIT: eh, it didn’t break this time but my shenanigans on this page seem to be poorly affecting other pages… NONE of these avatars are working now and I think it’s because a network request is “stuck”. [image]

Today: I reloaded the page with lazy, and it loaded fine: [image] I then loaded the page without lazy, and: [image] :person_shrugging:

So I guess that means it’s unlikely lazy= is the cause of the issue? At least that’s one thing ruled out :sweat_smile:

Firefox is sometimes unable to load/render previously cached images (avatars)

Product Support

piffy May 27, 2024, 7:02pm 2

I’ve seen this myself on Firefox. Don’t know if it’s relevant at all but my site uses bunny.net as a cdn

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Firefox is sometimes unable to load/render previously cached images (avatars)

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