What is the bug where you made the initial changes? We should link to the bug the regressions caused by it (I've seen at least a couple regressions filed mentioning this post on dev-platform rather than the bug where the regression was introduced).
- Marco. Il 13/03/19 22:14, Dave Townsend ha scritto: > A quick update here. After hearing some feedback from folks I've filed the > following bugs that I should have a patch up for in the next day: > > https://bugzilla.mozilla.org/show_bug.cgi?id=1535021 Don't show the profile > manager when the default profile was selected and an existing instance is > running. > https://bugzilla.mozilla.org/show_bug.cgi?id=1535144 Return -new-instance > to its previous behaviour. > > On Mon, Mar 11, 2019 at 11:35 AM Dave Townsend <dtowns...@mozilla.com> > wrote: > >> Woah this email got long. How Firefox considers whether to pass off to an >> existing instance of Firefox or continue launching a new one turns out to >> be more complex than you might expect. I'm mostly interested in making >> folks aware of and giving feedback on how this works after I've changed >> some things so feel free to jump down there. But I figured some folks might >> find some context in how things work currently. For that, read on! >> >> One of the goals of pushing to a profile-per-install model for Firefox is >> allowing users to run different versions of Firefox side-by-side without >> the additional hassle of editing shortcut files or running from the command >> line. This has meant changing the "remoting" code, which searches for >> existing instances of Firefox and passes command line arguments to them >> instead of starting up normally. I landed the changes to this a couple of >> days ago and I thought it was worthwhile explaining what has changed since >> it might not be exactly what you expect. And if that is the case figure out >> whether it makes sense to make any changes. >> >> *So first, a quick recap of what remoting has done in the past, because it >> varies from platform to platform...* >> >> OSX is the easy case. Firefox doesn't handle remoting at all. OSX does it >> all, assuming you are running Firefox by running an app bundle or a dock >> icon. OSX sees that an existing Firefox is running and just sends it a >> message, a new Firefox instance doesn't even start. I've made no changes >> here. >> >> Windows is the slightly more complex case. When run Firefox attempts to >> find an already running Firefox. If one exists it passes its command line >> off to it and quits. The -no-remote command line argument is a way to >> bypass this behaviour, running with it will stop the new Firefox from >> attempting to find an existing instance or becoming and instance that can >> be found by other instances. Basically there can only be one Firefox open >> that can be found by future invocations. The -new-instance command line >> argument is parsed on Windows ... and then ignored. >> >> Finally there is Linux. The more exciting case. Unless -no-remote or >> -new-instance are passed on startup linux will search for an existing >> version of Firefox based on a few criteria .. which varies a little >> depending on whether we're using dbus remoting or X remoting. We use X >> remoting if we are using X11 windows, and dbus if not (and dbus is >> supported). In both cases on startup Firefox attempts to find an existing >> instance of Firefox with the same remoting name (or you can provide a >> different remoting name with -a on the command line). dev-edition has one >> remoting name, all other versions of firefox have a different one. If there >> is more than one .. which one wins seems undefined. You can additionally >> pass "-P <profile name>" in which case Firefox will only select an existing >> instance running the named profile. On X remoting there are a few extras. >> Passing "-a any" on the command line will find any running Firefox >> regardless of remoting name. Passing "-u <username>" will consider >> Firefoxen run by the given user (otherwise it only looks at those run by >> the current user). -no-remote means FIrefox doesn't register itself to be >> found by future instances. -no-remote or -new-instance means we don't look >> for existing instances on startup. >> >> So that's all rather complicated. To make matters more fun the linux and >> windows implementations are handled by totally separate code running at >> different times during startup. The two key problems here were that windows >> completely didn't support more than one instance running, unless all but >> one were -no-remote, and linux was horribly complex and again unless you >> ran with command line arguments didn't support more than one Firefox at a >> time. We wanted something that allowed running Firefox release and Firefox >> beta and Firefox nightly with no special arguments at the same time. >> >> So I have done three things. Removed support for some of the things Linux >> supported. Made the code a lot more shared between windows and linux so >> things happen at the same time regardless of platform and both platform >> have what should be identical behaviours. Changed the order of when some >> things happen. >> >> What did I remove? Support for remoting to a different remoting name and a >> different user. Both seem unlikely to be useful for normal use cases, the >> latter frankly feels like a security risk. >> >> *How does it all work now?* >> >> OSX hasn't changed, maybe we'll want to do some changes here, but for now >> it already allows running different versions of Firefox so long as they are >> using different profiles, which is the default. So for the rest of this >> assume I'm talking about Linux (dbus or x11) and Windows. They all should >> behave the same. >> >> The new remoting does everything based on profile. When starting Firefox >> we do normal profile selection, which includes considering any -P and >> --profile command line arguments. Once we've selected a profile we attempt >> to find an existing Firefox instance using that profile. If one is found we >> send it our command line arguments and quit. If not continue start up. >> Since different installs of Firefox use different profiles by default this >> generally means that running Beta would pass off to an existing Beta. Same >> for other installs. It also means if you do "firefox -P foo -url >> www.google.com" we'll open that url in profile Foo, either by using an >> existing Firefox using profile Foo or by starting with profile Foo. >> >> -no-remote and -new-instance still exist. Right now they do the same >> thing, they make Firefox not look for existing instances and not listen for >> remoting from future instances. They are pretty pointless now though, the >> only case where they would have an effect is when a second instance is >> trying to use a profile that is already used by an existing instance ... at >> which point we'll show the profile locked dialog on startup and refuse to >> startup anyway. >> >> The most visible side-effect that folks have started seeing from this >> change is caused by waiting for profile selection to occur before >> attempting to remote. If Firefox is configured to always show the profile >> manager on startup then attempts to open links from outside apps will cause >> the profile manager to show, because that is what selects the profile. >> Selecting the profile of an already running Firefox from the UI will then >> remote to that Firefox (barring a bug that should be fixed in the next >> nightly), but this is a change in behaviour and honestly not one I'd >> spotted before landing. In some ways the new behaviour kinda makes sense >> (if there wasn't already a Firefox running you'd get the profile UI >> previously too) but I can see how it is confusing too so it might be worth >> considering changing something here, we'd just have to figure out what >> profile we should use in this case. >> >> The other thing that might be confusing is that the version or install of >> Firefox you try to launch doesn't affect which version or install of >> Firefox you might end up remoting to. This has always been the case on >> Windows and normally the case on Linux, unless you pass an extra command >> line argument though so I'm not too concerned here. >> >> Hopefully this all makes sense. I'd like to hear if folks think that this >> is the wrong way to support this and if you spot any issues with it that I >> haven't. >> _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
