1704204 - Some pictures not appearing at correct size at WordPress

Status: RESOLVED INVALID

(Core :: Layout: Images, Video, and HTML Frames, defect)

Description

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Attachment: Shapers-inset-pic-CorrectL-&shrunkenR.png

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:87.0) Gecko/20100101 Firefox/87.0

Steps to reproduce:

After referring a glitch to WordPress Support, they suggested Bugzilla. In my 13-year-old blog some pictures are sized to less than full-column-width, either set left, or set right, with text running round them. There are three examples in this page:
https://shapersofthe80s.com/seismic-shifts/mclarens-requiem-to-myself/

Actual results:

Within the past two years some of these inset pix (not all) now appear shrunken within their grey borders, while their self-contained captions still show as full-out. They appear like this in Firefox and Opera Browsers, but not in Safari where they look correct. WordPress support note that the blog's Coraline theme has been retired though should still respond to my iMac's OS10.14. Support also noted shrunken images on his laptop monitor (Apple “retina” display) . SEE screengrabs attached.

Expected results:

WordPress support reported: "The scale change is not due to an issue with the theme itself, since the coding has not changed in some time. Instead it looks like a change to the way the Firefox browser handles images on hi-DPI (retina) displays has taken place." And suggested this report to Bugzilla. I haven’t formed any consistent pattern as to why some pix old and new are affected but not others. Here's another page where some but not all its inset pix are shrunken - https://shapersofthe80s.com/2010/05/16/2010-%e2%9e%a4-how-real-did-1980-feel-ex-blitz-kids-give-verdicts-on-tonight%e2%80%99s-play-worried-about-the-boy/

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Graphics: WebRender' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Comment 2

[Alice0775 White]

I can reproduce on windows10 when zoom in(ctrl++).

Comment 3

[Emilio Cobos Álvarez (:emilio)]

This works in FF 48, but of course a narrower regression range is needed.

I'll take one on monday probably if nobody gets to it sooner.

Comment 4

[Alice0775 White]

Regression window(Windows10, set layout.css.devPixelsPerPx=1.20):
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=e1db820796b22bb3cbdafad7e6aabab4cc6a6ab2&tochange=94d7f0e1c4d0390450028972cfeb65e0550b9892

Comment 5

[Emilio Cobos Álvarez (:emilio)]

Yeah, so this was a regression from bug 1149357, but it is in fact a site bug. The relevant image has:

<img [...] src="https://shapersofthe80s.files.wordpress.com/2010/04/vertmekcomb.jpg?w=170" srcset="https://shapersofthe80s.files.wordpress.com/2010/04/vertmekcomb.jpg?w=170&amp;zoom=2 2x" [...]>

What that srcset is intended to do, is providing a 2x image for HighDPI displays. However, the image is the same size as the src image, which means that its intrinsic size would be halved.

So I suspect either the site shouldn't be setting srcset, or the &zoom=2 is intended to provide a twice-as-big image, and that is somehow not happening.