I did the same at first. Then I went with this instead:

* {
    border-radius: 3px !important;
}

I'll fix things one by one slowly, probably until the next UI overhaul comes. Then start over.

That's nice to hear. Though, haven't tried II but I was quite mediocre in my opinion. It was not a game that captivate me like older FF titles.

I only bought a couple titles from Steam in the last 3 years and feel similar. However, going to GOG reignited my feelings, so there is that too.

I buy mostly from GOG since last year and if I find everything on GOG I would only buy from there too. For some games, I just upvote Dreamlist entry, maybe write a memory too. Some publishers eventually bring their games and I have no rush. I also buy games I already have on Steam if I see a 90% discount or so. Ultimate goal is to gather everything of course but that will take years.

The question should be "How comfortable is this" instead.

This is a nice collection by the way.

No problem! I wish I could've helped. :)

It seems they once had a similar design idea in mind but it didn't make to final design apparently, at least for your second question.

This update is actually nice and is in the right direction in my opinion but it's still not as convenient as Sidebery.

Thanks! It went well for me too. They brought back compact density option by the way, we don't have to go to about:config for it anymore.

Well, the last two UI changes were a disaster for me so I was expecting something bad honestly. This one wasn't a headache. It was just... too round. :)

Hi again!

1. As far as I see, separating tabs from sidebar is not possible currently. However you can use an extension like sidebery and modify Firefox's sidebar from CSS. Sidebery itself is quite customizable.

2. Same as 1.

3. That space doesn't exist for me and I cannot replicate it on two of my devices. It could be related to Windows' own window decoration. I'm on Linux, so no idea.

Sorry, couldn't help with your requests.

Finally updated Firefox.

After the update surprisingly nothing was broken, however everything was so round I had to revert that. I lazily removed every bit of roundness by adding

* {
    border-radius: 0px !important;
}

to userChrome.css. I might try adding it part by part later but probably won't since this works.

I also went to about:config and set sidebar.revamp to false so the new sidebar-header is removed and I don't have to change anything on my old css config.

Edit: By the way, my css config is like Frankenstein's monster for a long time already, been editing the same file for the last 10 years. Probably should rewrite all some time.

Later edit: Just made the radius into 3px, it's easier on the eyes now. However now I have to edit it part by part because I still don't like some roundness even if it's tiny bit.

I too have a heavily modified CSS and love to use vertical tabs for a while. However, I haven't updated yet and will revisit this post tomorrow, hopefully.

No idea about the new UI so won't be able to comment now. My current setup is, replacing sidebar entirely with Sidebery and disabling the sidebar via CSS. I just hope I don't have to change this, or at least adapt my setup into this. Sidebery is pretty customizable.

Also I'm pretty sure that space can be removed via CSS.

Good night, for now. :)

So, tomorrow will be the day I try to fix my Firefox setup, again. I have heavily modified CSS and Sidebery vertical tabs. I hope it won't take long. Definitely not in the mood for this. -_-'