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Reviews for Don't "Accept" image/webp

Don't "Accept" image/webp by jscher2000

4,4 Stars out of 5
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Review by Firefox user 12363114
by Firefox user 12363114, 4 jaar gelede
Worked for about 5 minutes and then failed, allowing webp files through. I thought it was great while it lasted. It might be that the web site anticipated the add-in and bypassed it's functionality of not recommending webp images.

Developer response

posted 4 jaar gelede
The extension should discourage servers from recompressing JPG and PNG images as WebP images -- typically without changing the file name/extension. Can you share a URL of a page that recompresses JPG and PNG images despite the extension? Perhaps I can figure out a workaround.

In case the problem is cached images from a previous visit to the page, you can clear Firefox's web cache: https://support.mozilla.org/kb/how-clear-firefox-cache

Note: the extension doesn't block pages like https://developers.google.com/speed/webp/gallery1 from using WebP images when they are part of the design.
138 reviews
  • by LEXAR-SDHC, 11 dae gelede
    I wonder how
  • by 64fanatic, 2 maande gelede
    Not working atm. Go to Youtube Community and try to save an image.

    Developer response

    posted 2 maande gelede
    Hi, sites decide what format to serve based on different criteria. This extension only changes the "Accept" header. Some sites check the user agent instead (to see whether it's a modern browser). If you had the problem with a post on the Community tab of a YouTube channel, I see it, too. I don't think Google offers those images in alternate formats. (If I try to download one using the Internet Explorer 11 user agent, I still get WebP.)
  • by Firefox user 18285487, 2 maande gelede
    Great idea. Lossless WebP is generally a superior alternative to Png (except it cannot handle HQs beyond 16k on a side), but when you get served a webp on a web site, there is a 95% chance it is just a Jpg that has gone through another round of lossy compression, a different type, at a lower bit rate = worse quality (fewer fine details).

    In an ideal world, the digital master would be encoded as both Jpg/Png and Jxl, and the browser would have an option built in to preference one format over the other. JpegXl is the best new format. Jpeg2000 was decent but I don't think any browsers support it, and it even has a lossless format.
  • by blahblah, 4 maande gelede
    Doesn't work.
  • by Firefox user 13807639, 4 maande gelede
    TipTop, endlich wieder vernünftige Datei-endungen
  • by Dan, 5 maande gelede
  • by lucianoinso, 5 maande gelede
    Works as intended!
  • by oguz, 5 maande gelede
  • by NBA20, 6 maande gelede
    Works as intended. Thank you very much jscher2000
  • by Brixter, 6 maande gelede
    Good
  • by Shela, 9 maande gelede
  • by Major Gear, 9 maande gelede
    This addon installs easily and does what it says on the tin. I recommend this addon.
  • by Alive, 9 maande gelede
    Works great so far!
  • by Stephen, 9 maande gelede
    Fantastic! Does what it's supposed to and doesn't get in the way.
  • by Firefox user 11803080, 9 maande gelede
  • by Bella White, 10 maande gelede
    Really helpful
  • by Firefox user 18347256, 10 maande gelede
    Extremely useful and efficient, now I can save an image in it's original jpg or png format, instead of paying 2 conversions jpg-webp then webp-jpg. Should be the default when saving a jpg or png image.
  • by Asmodeus, 10 maande gelede
    this is one of the most convenient and helpful add-on in the world, it made my life so much easier when using Reddit and is the sole reason I switched to Firefox.
  • by Eru, 'n jaar gelede
  • by Firefox user 14506206, 'n jaar gelede
  • by CodeIcannot, 'n jaar gelede
    After using this add-on for a long time, I'm only giving it 3 stars, because it's very unclear to me, if it's actually accomplishing anything...? There are lots of sites that keep pushing webp and avif files, even when this add-on is in use, and it feels like the number of those sites is increasing, all the time.

    Developer response

    posted 'n jaar gelede
    Unfortunately, this add-ons is only effective on sites that pay attention to the "Accept" header. Other users have identified certain sites that ignore the change made by this add-on, such as NexusMods and PlayStation. These sites either no longer support legacy browsers, or require a legacy user agent (such as Internet Explorer 11) before sending legacy media formats. For cases like that, you could consider using a converter. I have one here on the Add-ons site called "Save webP as PNG or JPEG."
  • by Andrew, 'n jaar gelede
  • by sabrelion, 'n jaar gelede
  • by Firefox user 16974979, 'n jaar gelede
    I am so annoyed by the webp format as someone who collects art references on the internet for private use, and no reference program supports webp. Webp is a scourge on the internet and I am glad this plugin exists.
  • by Firefox user 18135064, 'n jaar gelede
    Thank you