MacOS – Apple website animations do not work on Safari 11

Firefox

Firefoxes is a shell scripts that will install all major versions of Firefox on OS X, and set up separate profiles so you can use them simultaneously. Currently it installs:

• Firefox 2.0.0.20
• Firefox 3.0.19
• Firefox 3.5.9
• Firefox 3.6.28
• Firefox 4.0.1
• Firefox 5.0.1
• Firefox 6.0.1
• Firefox 7.0.1
• Firefox 8.0.1
• Firefox 9.0.1
• Firefox 10.0.2
• Firefox 11.0
• Firefox Beta
• Firefox Aurora
• Firefox Nightly
• Firefox UX Nightly

You can set it up so it only installs the specific versions you want.

Optionally, the script can install Firebug for each version of Firefox too.

It will also set icons that contain the version number:

Safari

For Safari, check out Multi-Safari.

Chrome/Chromium

For Chrome/Chromium, install any version you want, change the app name from Chromium.app to e.g. Chromium 19.app for clarity, then disable auto-updates for that version.

Opera

Download old Opera versions here: ftp://ftp.opera.com/pub/opera/mac/

IE

Get VirtualBox and then run this ievms script. It will automatically download legal Windows images for testing purposes and set up virtual machines for every IE version you need.

The difference is likely to do with the architecture and interprocess communication choices of each browser.

Modern web browsers render pages in separate processes. Apple has a framework called IOSurface that provides a streamlined way for one process to pass an image to another process. This framework was introduced in Mac OS X 10.6, aka Snow Leopard, for the latest iteration of QuickTime.

QuickTime uses IOSurface to offload movie decoding to separate processes. With no decoding to do, the QuickTime Player application is left dealing solely with the user interface and showing images provided by the decoding processes.

I suspect Safari has learned from QuickTime and is using the same techniques. Web pages are offloaded to other processes, rendered, and passed back.

Could Chrome and Firefox do the same thing, absolutely. The challenge is ensuring the thread dealing with the user responds quickly and is not delayed waiting for the rendering to update.

Chrome does use separate processes and appears to use IOSurface on the Mac; this bug talks about improving Chrome's use of IOSurface.

IOSurface is a public framework available to any Mac OS X 10.6+ application. However there is little documentation and it is Mac specific.

This is all conjecture.