> and therefore did not liked it, when frequently changes broke their setup.
Which is unfortunately an inherent problem with our legacy customization approach.
And it is clearly not something the vast majority of users want, if they left Firefox for another browser that appears to them less customizable but more stable. We have run numerous user studies about what users actually care for and they have all informed what Firefox is going to be in the future.
about:permissions was an incomplete experimental UI, but a fully functional replacement is high on our priority list. We are waiting on a new design from the UX team at the moment.
This is exactly right that X means "close" or "hide this thing" and this is what it does in this case as well: it removes the non-default setting and hides the list item.
There have been a number of user studies done by Mozilla and other browser vendors that clearly show end users only have a basic grasp of the security properties of the web. So yes, more details in main UI elements leads to confusion. It's just 2 clicks for those of us who know what a certificate is (Ctrl/Cmd-I is even faster).
Three, actually. One on the i+lock icon pair, one on the right-pointing arrow, then one on "more info". If I'd need more details (like issue and expiry dates, which is pretty common thing to be interested in), then it's 1 more button "view certificate". And if I'd happen to be interested in certificate public key properties (algorithm and key size) it's a really long story, 6 clicks away from the address bar.
It certainly makes sense to not show something right away, on the first click. But the current UI hides quite essential information (to those who can understand it) way too deep. I'm really not persuaded it would hurt usability and confuse users if such information would be 2 clicks away, rather than 4-6.
(And, really, it mustn't hurt to show at least "have I visited this page prior to today? yep, 234 times" on the very first click. And probably won't confuse anyone much to also see something like "TLS1.2, modern ciphers" or "TLS1.0, legacy ciphers".)
> Ctrl/Cmd-I
Toggles bookmarks sidebar for me. I'm unaware of any shortcut to open page info.
You are pretty much describing the Firefox architecture. We are invoking Firefox UI code from scratchpad all the time when prototyping things. Some parts of the UI do not use standard Web APIs (e.g. XUL and XBL), as there are different opinions on how the web platform should evolve to fulfill those needs, but if you include all the experimental technologies to this web kernel, we are already there.
Mozilla has been paying the main Firebug developer for a long time to work on it, but I've never heard of an open source project that would like to be "acquired", whatever that means. If hiring all of the project's developers is what you mean, quite a few of them had high profile jobs already, so funding wasn't an issue here. As for the reasons why simply incorporating Firebug into Firefox wasn't a viable solution, see the original post.
Which is unfortunately an inherent problem with our legacy customization approach.
And it is clearly not something the vast majority of users want, if they left Firefox for another browser that appears to them less customizable but more stable. We have run numerous user studies about what users actually care for and they have all informed what Firefox is going to be in the future.