Is there a way for the new window animation in Firefox for Mac to be disabled? Safari does not do this, but firefox has a... ~100ms animation for new windows that's extremely frustrating for those of us who do not use tabs (Apple's Exposé/Mission Control obsoletes them). I haven't found a configuration in about:config, although I've been able to disable a few others.

This seems to be more of a thing on macOS and not by Firefox.

ex: https://apple.stackexchange.com/questions/14001/how-to-turn-off-all-animations-on-os-x

I am on Windows O/S and never saw the window animation your talking about?

Because you are using Windows and not macOS.

I found a way to reduce a lot of delays to zero, editing some about:config files. There was a large list, but I can't remember what exactly I followed, and I don't remember which of the many things I changed made a different and didn't.

I do not know whether the ui.prefersReducedMotion pref includes this animation. You can give it a try and create a new Number pref named ui.prefersReducedMotion on the about:config page and set its value to '1'.

• set its value to 0 if you want to see animations
• set its value to 1 if you want to block animations

You can open the about:config page via the location/address bar. On the warning page, you can click "Accept the Risk and Continue" to open about:config.

• https://support.mozilla.org/en-US/kb/about-config-editor-firefox