Toolbar button icons (icons_hidpi.png) are mangled in some zoom levels in Blink-based browsers (Chrome/Opera) on a Retina Mac.

[Jim Douglas]

Steps to reproduce

1. Go to ​http://ckeditor.com/demo#full in Chrome or Opera on a Retina Mac.
2. For a baseline, start with Actual Size (View->Actual Size or CMD 0); toolbar icons are good.
3. Now check various zoom levels (View->Zoom In/Zoom Out or CMD+/CMD-.

Expected result

Tool button icons are correct at any zoom level.

Actual result

Tool button icons are correct at: 50%, 75%, 100%, 125%, 150%, and all higher values.

Tool button icons are wrong at: 67%, 90%, 110%

Other details (browser, OS, CKEditor version, installed plugins)

Mac OS Yosemite 10.10.5, Retina display.

Problem occurs in Chrome "Version 44.0.2403.155 (64-bit)" and Opera "31.0.1889.174".

Problem does not occur in Safari "Version 8.0.8 (10600.8.9)" or Firefix 40.0 on the same machine, or in any browser on a Windows 8.1 non-retina machine.

[Jim Douglas]

​http://ckeditor.com/demo#full in Retina Mac Chrome, zoom 90%.

[Wiktor Walc]

Works for me, zoom 90% attached.

Version 44.0.2403.155 (64-bit) Yosemite 10.10.3 (14D136)

[Jim Douglas]

Looks like it's this two-year-old Chromium bug: ​https://code.google.com/p/chromium/issues/detail?id=260319

Another similar report: ​http://stackoverflow.com/questions/24517865/svg-sprite-icon-background-position-appears-off-in-newer-version-of-chrome

[Wiktor Walc]

Disregard my last comment. Issue confirmed. I was testing it on my primary screen, while the secondary screen is retina. Attached is my result.

[Wiktor Walc]

Hidpi support was added in 4.2, thus the version. It's not a regression.

[Wiktor Walc]

Note: as described in TC, the issue occurs only when someone changes the zoom level when CKEditor is loaded. If you set the zoom level first and then open a page with CKEditor, then the editor works fine.

[Jim Douglas]

Fixed in Chrome 49.0.2623.75: ​https://bugs.chromium.org/p/chromium/issues/detail?id=66498