What OS? If windows, home or pro? If windows, are you running any security software besides MS Defender? What version of Firefox? I only get jpeg when saving the image. see screenshot

Jon,

What OS? If windows, home or pro?

Windows 7 Pro . Yea, it still works

If windows, are you running any security software besides MS Defender?

No. Periodic scan with Malware Bytes.

What OS? What version of Firefox?

115.22.0

When I go to the Meetup event, open the photo, and hit the download link FF opens up a new tab displaying ONLY the image. When I right click on the image to Save Image As... the only option is AVIF. JPG is not listed.

Apparently FF has downloaded the JPG from the source and has converted it to AVIF.

Here is a link to the Meetup event photo album so that you can follow the download process: https://www.meetup.com/greenway-cyclists-of-the-triangle/photos/35413305/

I am also attaching a screenshot of the Save Image dialog screen.

Thanks, Steve

I just downloaded the jpg as a jpg same as Jon - no issue on pclinuxos with FF 139.0.4. Your meetup link wants a signup. If you are familiar with using about:config, do a search on avif - there are several settings there which may interest you but myself I am still struggling with HEIF. May be a Windows issue, someone else here can probably offer more input.

OT still riding an '83 Cannondale SR 900.

Hello,

Well, I tried changing the AVIF file processing in the settings to "Always Ask". This had zero effect because the original file is really a JPG!

Here is another possible clue... The tab for the new window that the photo opens in says something about AVIF but the text is chopped of and not readable. Is there any way to expand the tab header to read the full message?

Thanks, Steve

The AVIF is coming from somewhere because the site is serving a jpeg as you can see in the code. see screenshot I also have Win7, let me boot it up and see what happens. You can also try Refreshing Firefox. https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

Win 7 was extremely painful, but was able to replicate the issue. see screenshots Even changing how the app is handled made no difference. Someone closer to dev will have to chime in.

What has the group tested so far?

• Firefox 139 => JPEG
• Firefox 115 on Windows 7 => AVIF

Is it a Firefox 115 issue or a Windows 7 issue?

Firefox doesn't convert images, but sites decide what image formats to send Firefox based on modernity of your browser and the Accept header that Firefox sent with the request.They sometimes send more compressed WebP or AVIF-format images to save on bandwidth. That second one was the reason I created my add-on, Don't "Accept" image/webp, which has an option to stop mentioning compatibility with PNG and AVIF in the hope that sites then will send a traditional format.

Is there any way to expand the tab header to read the full message?

There is a minimum tab width setting, but it will affect all your tabs. Although it's a bit slow, you can hover the mouse pointer over the tab to see the full title. Or call up Page Info using Ctrl+i.

Win 7 was extremely painful, but was able to replicate the issue. see screenshots Even changing how the app is handled made no difference. Someone closer to dev will have to chime in.

Thanks for checking this out!

Steve_Sr. said

Is there any way to expand the tab header to read the full message?

There is a minimum tab width setting, but it will affect all your tabs. Although it's a bit slow, you can hover the mouse pointer over the tab to see the full title. Or call up Page Info using Ctrl+i.

Here is the page info. Thanks for the Ctrl+i tip!

What has the group tested so far?

• Firefox 139 => JPEG
• Firefox 115 on Windows 7 => AVIF

Is it a Firefox 115 issue or a Windows 7 issue? Firefox doesn't convert images, but sites decide what image formats to send Firefox based on modernity of your browser and the Accept header that Firefox sent with the request.They sometimes send more compressed WebP or AVIF-format images to save on bandwidth. That second one was the reason I created my add-on, Don't "Accept" image/webp, which has an option to stop mentioning compatibility with PNG and AVIF in the hope that sites then will send a traditional format.

Well, somebody is lying! The URL says that the image is a JPG or is this just mis-reporting to make browsers happy in case that they can't handle an AVIF image? Is meetup really sending an AVIF image? So if FF doesn't convert then this would be the case.

If this is true would your add-on have any effect on this issue?

Thanks, Steve

Some server farms substitute WebP or AVIF-compressed files for JPG and PNG images without changing the file name. That creates the mismatch between the file extension and the internal format. Browsers don't really care about the file name, they typically handle files based on the Content-Type header.

> If this is true would your add-on have any effect on this issue?

It works on sites that make the substitution decision based on the "Accept" header. It doesn't work on sites that key off your browser version.