Bug 274827 – REGRESSION(2.45.1/2.45.2): [GTK] All PNG images look jagged

• Status: RESOLVED
• Resolution: FIXED
• Component: WebKitGTK

[Michael Catanzaro]

Created attachment 471535 [details]
The logo

The attached PNG image is used by Red Hat for its Google account logo. Since 2.45.1 or 2.45.2, the logo looks bad when rendered in the upper right hand corner of Google domains like calendar.google.com or mail.google.com. I'm attaching the image itself, a Before screenshot showing that it's rendered fine in 2.44, and an After screenshot showing it's rendered badly in 2.45.

It might be related to the switch to skia.

Note: the image is named "logo.gif" in the grand web tradition of using misleading file extensions for images. It's a PNG.

[Michael Catanzaro]

Created attachment 471536 [details]
Before (2.44)

[Michael Catanzaro]

Created attachment 471537 [details]
After (2.45)

[Michael Catanzaro]

Created attachment 471539 [details]
Second image

Here's a second image. This one is only conditionally broken. It displays fine when loaded in Epiphany on https://www.vox.com/money/352116/whats-really-happening-to-grocery-prices-right-now. But if you display it in Newsflash, it looks bad. It's strange that the result is different in the two applications. My first guess was that it displays badly at small sizes, but that doesn't seem to be correct; it looks fine at small sizes in Epiphany, and still looks bad at bigger sizes in Newsflash. Newsflash must be doing something differently.

(Newsflash is supposed to be using WebKitGTK 2.44.2, but it's currently using 2.45.2 because I messed up and upgraded the GNOME 46 runtime to 2.45.2 by mistake.)

[Michael Catanzaro]

Created attachment 471540 [details]
Screenshot of second image displayed in Newsflash

[Michael Catanzaro]

Finally I've noticed this bug in the reddit.com logo. That's by far the easiest reproducer. Just go to reddit.com and note that the logo looks bad.

[Michael Catanzaro]

Another easy reproducer: https://discourse.gnome.org/

[Michael Catanzaro]

Seems like all images on all websites are affected by this issue.

[Patrick Griffis]

Pull request: https://github.com/WebKit/WebKit/pull/31895

[EWS]

Committed 282492@main (1efcb4f3b8fb): <https://commits.webkit.org/282492@main>

Reviewed commits have been landed. Closing PR #31895 and removing active labels.