I hear about "FF performance issues on Mac" and I just don't get it.

I believe all of the people who report this, but it's not something I experience. Here's my usage pattern:

- 50+ hours in a browser each week

- Regular use of both FF and Chrome with very occasional use of Safari (I'm a developer of web apps)

- FF has been my primary browser for 15 years or so

- Used on a variety of Macs (2006, 2008, 2011, 2013, and 2015 MBPs with 8-16GB RAM)

- Running uBlock Origin in all browsers FWIW

...so, anecdotal, but pretty extensive.

I never had major problems with FF in the pre-Quantum days. Chrome always felt snappier than FF, and Safari felt snappier than both, but the differences were not huge and FF was "fine." And now since Quantum, FF is on par with Chrome for me in general.

The one time FF feels like a pig for me is on Google-owned web apps like Gmail.

For many years, Gmail and Gsuite apps were lightning fast on FF. But in the last few years it has gotten slower and slower on everything but Chrome. Hmmm, wonder why.

Firefox on OS X (Macbook Pro 2017 and 2015):

- uses 100% CPU even when idle

- frame rate drops to 2-3 per second for 5-10 seconds when switching tabs

- causes other programs to not work properly because it is using too much CPU

I have tried uninstalling the browser and re-installing OS X but it didn't solve those issues. I read somewhere it is a bug that pops up when you have display resolution scaling on and I think it applies to me because I have two 4k monitors set at 2x scaling.

    uses 100% CPU even when idle

That sucks.

Anecdotally, I've never seen this, even when I had 1 external 4K and 1 external 2K connected. The whole OS was kind of sluggish at that point, but that was definitely asking a lot out of a puny integrated 3-year old laptop GPU so eh.

Just did a quick informal test with my current setup:

- MacOS High Sierra.

- 2015" MBP with no discrete GPU.

- Single 4K external monitor, 3008x1692 scaled resolution.

- uBlock is off.

With only a single blank tab open FF uses 0% CPU as expected. I opened three tabs: Facebook, Espn.com, and MSNBC.com. There was a brief flurry of CPU activity as the sites loaded, and FF's processes are now idling comfortably at 0-1%.

I repeated the process with Chrome and results were similar. One difference is that Chrome spawns 10x as many processes, but they seem to consume less memory each.

In both FF and Chrome, there's a palpable (500 or 750ms?) delay when switching tabs. In my experience a lot of Mac apps behave that way at scaled 4K resolutions.

I repeated this informal test in Safari and it "feels faster"; less CPU spike on initial site load and switching browser tabs feels close to instant.

Entirely anecdotal but I have noticed huge issues with Firefox when I hook my laptop up to a 4k display. My normal display is 1080p and no issues on the same machine.

Well, the last update to Adwords aka Google Ads is now a clunky piece of shit on Chrome and FF.

I don't know if Google has gone too far with the A/B split testing and are picking winners solely on a most ad revenue metric or if they abandoned UX testing altogether. I suppose it could be a bit of both. May be their decision making AI is secretly optimizing Google in a destructive direction.. who knows.

I love how Safari sips battery on OS X, but its performance is glacial in my experience. With Chrome I can, for example, type “was” and hit return at normal typing speed and expect the browser to have autopopulated “washingtonpost.com” from my history and take me there. With Safari on the same newer high end macbook pro, autopopulate takes up to a few seconds, so hitting return takes me to the page half of the time and searches for “was” the other half of the time. Pages seem to take longer until the first meaningful content loads, too.

I wonder what the issue is. My experience with safari on my old macbook air is speedy with no power problems.

I switched back to Chrome recently because the ublock origin port on Safari has been pretty broken recently. Setting third party domain blocking options in advanced mode doesn't seem to work any more (can't save the settings) and the extension doesn't seem to be maintained any more, judging by the github repo.

The one major thing that keeps me from Safari is keyword searching. It's a major part of my browsing workflow and makes me so much more productive. Last I knew, you could assign hotkeys to bookmarks, but I don't think you could assign keywords and you couldn't use %s as a placeholder.

At first, I was confused, because I've been using this feature in Safari for years. But then I remembered that years ago I installed an extension called "Omnikey" that provides this: http://marioestrada.github.io/safari-omnikey/, https://safari-extensions.apple.com/details/?id=ec.mario.omn.... If this is the only thing holding you back from using Safari, install the extension and switch. It's been working so well for years that I forgot it wasn't built in.

Safari 12 no longer supports uBlock Origin. I discovered this over the past weekend. Without ad blocking, Safari is unusable for me.

EDIT: It seems AdBlock Plus has now come out with a new plugin that conforms to Apple's new API.

It does, if you enable it again (or reinstall it from the Safari Extensions directory). However, I get the feeling it will only last for this version, since they seem to be closing down on JavaScript extensions in general.