How is FF ugly? I don't find the UI very different from Chrome and Safari.

I don't know what it is, but I agree. There is something subtly and subconsciously going on that nudges me away from FF too. I think it's the loose feeling UI, the default smiley face icon of the chat that I don't know anyone uses, the paper airplane as the share icon. It's that there is still not unified search/address bar even if one would prefer it without running a poorly executed extension. It's that the tabs feel so childish with the far too rounded corners and loose padding and it's even the few pixels more of padding between the address bar and the tabs boundary. It's the small font of the address bar, it's the disproportionately large back button, it's the apparent lack of design and style requirements for extension icons that make them look blurry and generally shitty and bolted on in the UI, etc.

I know that all that maybe sounds rather petty and maybe there's something wrong with me and it's my biases for some reason, but it just all adds up to a fuzzy notion of childishness and less than "down to business" feel. I say that as someone that used to exclusively use FF and shunned Chrome for all the various reasons mentioned by others.

Care to list those reasons. Genuinely interested, and not sure which reasons you are referring to.

I don't get how he thinks it's ugly or different.

Not only is it very similar but, unlike Chrome or Safari, every aspect of it is customizable so you can make it look however you want. Out of the box you can rearrange the the UI elements to match Chrome or Safari.

I absolutely hate the FF UI. I WANT to use FF, I actually switched a few months ago and did it for a couple of months. I THINK my problem (I say think because I feel like someone will measure the pixel and say I'm wrong) is that it feels like there is a ton of wasted space between the tabs, above the tabs. etc. I can't control the size of the top bars and they're huge compared to chrome. I'm a fan of tiny icons and very, very compact UIs so that I can get more on the screen at once. Here's my comparison on a 28" monitor https://www.dropbox.com/s/k32gln7s3ev5a7t/Screenshot%202016-...

You might try the "Custom Tab Width" add-on to shrink your Firefox tabs. I also like to set my toolbar bookmarks' names to an empty string, so my toolbar is just a bunch of bookmark favicons.

https://addons.mozilla.org/en-US/firefox/addon/custom-tab-wi...

Hang on the chrome UI at the top takes up a couple of mm more vertically than the FF one. What other differences are there?

For me it's the other way around, I use FF for everything but dev sessions where I use Chrome (I prefer it's dev tools).

I tried breaking the habit for a while but I ended up opening FF all the time by muscle memory.

Plugins can get you a very compact ui: http://paste.click/XfPZOR

I'm also a fan of minimal as possible.

Perhaps give Tree Style Tabs on FF a try.

It's quite different, and because of XUL it also falls in the uncanny valley of looking like native widgets but not behaving exactly like them.

I'd say FF Developer Edition has the best UI out of all of them.

Nothing fits better next to a terminal window or a code editor.

Not all that different these days. http://imgur.com/qII55SM

The new FF UI has been out and stable for nearly two years now.

FF changes the UI very frequently. Even the last update from 42 to 43 had changes. I love FF and its my only browser but this is one of the most irritating things they do. Maintaining a standard UI is a must to retaining users (and keeping them upgrading).

I think you are underestimating the impact of the subtle nature of the differences. For me, it really kind of annoys me that FF seems to have a looser UI than Chrome. It's those couple of pixels of padding between address bar and tabs, it's the wider/longer tab due to padding, etc..

And now that I think about it, it's even things like the tab behavior where Chrome condenses tabs and FF just pushes them out of view an adds the disgusting scroll UI. Maybe that's a personal preference thing, but I would very much prefer having a dense overview rather than having what is essentially a nested scrolling.

I'm assuming there's an extension to merge the URL and search bars to get Chrome-like behaviour?

Yes you can enable search suggestions in the URL bar right in the Firefox preferences and hide the separate search box. I keep them separate because I don't care to have everything I type in the URL bar be sent to Google by default.

Exactly. The divide between address bar and search bar is a much under-appreciated privacy feature.

Omnibar is what you're looking for.

How can you live without FF's 3D DOM view?!

More seriously, FF's dev tools have felt more advanced than Chrome's for a while, including the ability to edit and resend an XHR request.

The 3D DOM view is really neat, but so far I haven't found a practical use for it.

For UI check out Firefox Dev Edition, clean and classy alternative. And the dev tools take some time, but they're likeable for sure.

The problem I have with FF dev tools is that json responses are hideous, just one long string. Where Chrome's look like json with expandable fields.

In the network panel (in FF), I have a structured view on JSON data, and can expand nested objects and arrays (like here https://mdn.mozillademos.org/files/7421/nm-response-json.png). Same goes for JS objects, which is a thing that bugged me long time.