Bug 270057 – Remove non-standard `webkitBackingStorePixelRatio`

• Status: RESOLVED
• Resolution: FIXED
• Component: Canvas

[Ahmad Saleem]

Hi Team,

I am raising this bug since I couldn't find same.

In Safari, currently we return `1` for 'webkitBackingStorePixelRatio' while in Firefox and Chrome - it is undefined.

I think we should remove this and align with other browsers.

Blink removed it in 2014 with following PR - https://src.chromium.org/viewvc/blink?view=revision&revision=170324

Appreciate if someone can share any input. Happy to do PR to do clean-up.

Also we have also few more legacy APIs, which I am happy to remove. Less code to maintain and also less fingerprinting as well on web.

Thanks!

[Radar WebKit Bug Importer]

<rdar://problem/123980544>

[Karl Dubost]

The PR for this is 
https://github.com/WebKit/WebKit/pull/25080

[Ahmad Saleem]

SVG link is gone - so chromium repo - https://github.com/chromium/chromium/commit/07ee81b34997614fcc8785df2aefaa3dd2092306

[Brent Fulgham]

Note that all major browsers seem to have an analog of this:

```
    context.webkitBackingStorePixelRatio ||
    context.mozBackingStorePixelRatio ||
    context.msBackingStorePixelRatio ||
```

We will want to make sure this doesn't break sites that try to use this for something.

[Ahmad Saleem]

(In reply to Brent Fulgham from comment #4)
> Note that all major browsers seem to have an analog of this:
> 
> ```
>     context.webkitBackingStorePixelRatio ||
>     context.mozBackingStorePixelRatio ||
>     context.msBackingStorePixelRatio ||
> ```
> 
> We will want to make sure this doesn't break sites that try to use this for
> something.

I have updated it to check for `moz` - https://jsfiddle.net/z069fcp2/3/

It is `undefined` in Mozilla Firefox.

Additionally - people are using following workaround - https://gist.github.com/callumlocke/cc258a193839691f60dd

leveraging `devicePixelRatio` to workaround the functionality provided by this API.

[EWS]

Committed 287523@main (bc5250e9ad63): <https://commits.webkit.org/287523@main>

Reviewed commits have been landed. Closing PR #25080 and removing active labels.