Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
On Thursday, January 7, 2021 at 7:07:05 PM UTC+1, Doug Thayer wrote: > On 1/7/2021 4:18 AM, Sebastian Zartner wrote: > > > On Wednesday, January 6, 2021 at 10:55:22 PM UTC+1, Doug Thayer wrote: > >> On 1/6/2021 1:51 PM, Mike Hommey wrote: > >> > >>> On Wed, Jan 06, 2021 at 01:46:52PM -0800, Doug Thayer wrote: > On 1/6/2021 1:44 PM, Mike Hommey wrote: > > > On Wed, Jan 06, 2021 at 01:30:00PM -0800, Doug Thayer wrote: > >> On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey wrote: > >> > >>> On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: > If you don't spend any time on Nightly in Windows 10, please feel > free to > disregard this. > > tl;dr: we're sometimes creating the first window differently than > usual, > >>> so > be on the lookout for breakages. > > On 2021-01-05, a change landed in Nightly which enabled the pre-XUL > >>> skeleton > UI [1]. This is a feature which allows us to create the first window > and > populate it with a non-interactive placeholder UI before we load > >>> xul.dll. On > some systems, this can mean we can give visual indication of Firefox > launching as much as 15 seconds sooner than normal (loading xul.dll > can > >>> take > a while). We're hoping this could be a big win for users who > experience > >>> very > slow startups, and we also hope it will improve the overall > snappiness of > startup even on fast systems. > >>> What does the placeholder UI look like? > >>> > >> Colors and layout can vary, but the basic look is this: > >> [image: image.png] > > The image attachment didn't quite work. > Woops. Here is a link: https://i.imgur.com/R4ynXW5.png > >>> Does the placement and the size of that window vary? > >> It does. It uses values persisted to the registry based on the most > >> recent run of the default profile, scoped by the path to the executable. > >> The registry values can be found at > >> HKEY_CURRENT_USER\SOFTWARE\Mozilla\Firefox\PreXULSkeletonUISettings. > > I am running Nightly 86.0a1 (2021-01-07) 64bit on Windows 10 on a freshly > > created profile and checked that the browser.startup.preXulSkeletonUI > > preference is set to true, though instead of seeing the UI I get a blank > > white window. I remember, I tested this feature like a month or two ago and > > it did work before. Is that expected? If not, please let me know what > > information is needed to track this down and I'll file a bug for it. > It could be expected. It's probably worth having some kind of disabled > reason listed somewhere at some point. For the time being, I'll > enumerate a few ways that this could get automatically disabled: > > 1) You could be running firefox.exe with command line arguments. We have > a finite list of command line arguments which are approved - if we see > anything outside that list we disable the skeleton UI. This covers, for > example, launching the profile manager, which is of course a window that > looks nothing like the typical main browser window. The list of approved > command line arguments is defined in code here: > https://searchfox.org/mozilla-central/rev/519f913527b0d9d5097d290d5731cff6b2991fe0/mozglue/misc/PreXULSkeletonUI.cpp#1570 > That was it. Thank you for the detailed hints! As I wrote before, I tried it on a fresh profile. And I called it via `-p test` from the command line. And my normal Nightly profile is called via `-p nightly`, so that's why I didn't see it. Without it it works. Would be nice if it worked with different profiles, though. Anyway, congratulations again! Sebastian ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
On 1/7/2021 4:18 AM, Sebastian Zartner wrote: On Wednesday, January 6, 2021 at 10:55:22 PM UTC+1, Doug Thayer wrote: On 1/6/2021 1:51 PM, Mike Hommey wrote: On Wed, Jan 06, 2021 at 01:46:52PM -0800, Doug Thayer wrote: On 1/6/2021 1:44 PM, Mike Hommey wrote: On Wed, Jan 06, 2021 at 01:30:00PM -0800, Doug Thayer wrote: On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey wrote: On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: If you don't spend any time on Nightly in Windows 10, please feel free to disregard this. tl;dr: we're sometimes creating the first window differently than usual, so be on the lookout for breakages. On 2021-01-05, a change landed in Nightly which enabled the pre-XUL skeleton UI [1]. This is a feature which allows us to create the first window and populate it with a non-interactive placeholder UI before we load xul.dll. On some systems, this can mean we can give visual indication of Firefox launching as much as 15 seconds sooner than normal (loading xul.dll can take a while). We're hoping this could be a big win for users who experience very slow startups, and we also hope it will improve the overall snappiness of startup even on fast systems. What does the placeholder UI look like? Colors and layout can vary, but the basic look is this: [image: image.png] The image attachment didn't quite work. Woops. Here is a link: https://i.imgur.com/R4ynXW5.png Does the placement and the size of that window vary? It does. It uses values persisted to the registry based on the most recent run of the default profile, scoped by the path to the executable. The registry values can be found at HKEY_CURRENT_USER\SOFTWARE\Mozilla\Firefox\PreXULSkeletonUISettings. I am running Nightly 86.0a1 (2021-01-07) 64bit on Windows 10 on a freshly created profile and checked that the browser.startup.preXulSkeletonUI preference is set to true, though instead of seeing the UI I get a blank white window. I remember, I tested this feature like a month or two ago and it did work before. Is that expected? If not, please let me know what information is needed to track this down and I'll file a bug for it. It could be expected. It's probably worth having some kind of disabled reason listed somewhere at some point. For the time being, I'll enumerate a few ways that this could get automatically disabled: 1) You could be running firefox.exe with command line arguments. We have a finite list of command line arguments which are approved - if we see anything outside that list we disable the skeleton UI. This covers, for example, launching the profile manager, which is of course a window that looks nothing like the typical main browser window. The list of approved command line arguments is defined in code here: https://searchfox.org/mozilla-central/rev/519f913527b0d9d5097d290d5731cff6b2991fe0/mozglue/misc/PreXULSkeletonUI.cpp#1570 2) You could be running with a theme other than the built-in dark, light, and default themes. I suspect this is not true because you said you're on a fresh profile. There are also a handful of other prefs which will disable the skeleton UI if they're not the value we expect, but again since you're on a fresh profile those should all be fine. 3) You could be running with any of these environment variables: https://searchfox.org/mozilla-central/rev/519f913527b0d9d5097d290d5731cff6b2991fe0/mozglue/misc/PreXULSkeletonUI.cpp#1690 4) You could already be running an instance of firefox with the same path. 5) You could have configured firefox to always open the profile manager. If it's outside those, then I think it's worth filing a bug or following up with me outside of the list? | ||| Also, regarding the registry values, I only see one for the theme with a key referring to the path of the Nightly executable. How will you handle different profiles? I hinted at this above in this message, but effectively we only allow the skeleton UI if we are running the default profile. So if you have firefox set up to always start the profile manager, or you specify a profile via the command line or an environment variable, then we simply bail out and don't show anything. Besides those issues, I'm really happy to see this coming. It improves perceived start up speed a lot, especially on less powerful machines. Sebastian ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
I'd like to second Mike's note. Congratulations to Doug, Emma, and everyone else who worked tirelessly on this feature to improve perceived performance. Your work will have a lasting effect and is a big step forward in Firefox's story as the fastest browser in the market. - Jared On Thu, Jan 7, 2021 at 10:55 AM Mike Conley wrote: > dthayer, > > Congratulations to you and emalysz for getting this enabled in Nightly! I > know it's been a long slog, but I think this is going to make a very > perceivable improvement to our startup responsiveness. > > -Mike > > On Thu, 7 Jan 2021 at 07:20, Sebastian Zartner > > wrote: > > > On Wednesday, January 6, 2021 at 10:55:22 PM UTC+1, Doug Thayer wrote: > > > On 1/6/2021 1:51 PM, Mike Hommey wrote: > > > > > > > On Wed, Jan 06, 2021 at 01:46:52PM -0800, Doug Thayer wrote: > > > >> On 1/6/2021 1:44 PM, Mike Hommey wrote: > > > >> > > > >>> On Wed, Jan 06, 2021 at 01:30:00PM -0800, Doug Thayer wrote: > > > On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey > > wrote: > > > > > > > On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: > > > >> If you don't spend any time on Nightly in Windows 10, please > feel > > free to > > > >> disregard this. > > > >> > > > >> tl;dr: we're sometimes creating the first window differently > than > > usual, > > > > so > > > >> be on the lookout for breakages. > > > >> > > > >> On 2021-01-05, a change landed in Nightly which enabled the > > pre-XUL > > > > skeleton > > > >> UI [1]. This is a feature which allows us to create the first > > window and > > > >> populate it with a non-interactive placeholder UI before we load > > > > xul.dll. On > > > >> some systems, this can mean we can give visual indication of > > Firefox > > > >> launching as much as 15 seconds sooner than normal (loading > > xul.dll can > > > > take > > > >> a while). We're hoping this could be a big win for users who > > experience > > > > very > > > >> slow startups, and we also hope it will improve the overall > > snappiness of > > > >> startup even on fast systems. > > > > What does the placeholder UI look like? > > > > > > > Colors and layout can vary, but the basic look is this: > > > [image: image.png] > > > >>> The image attachment didn't quite work. > > > >> Woops. Here is a link: https://i.imgur.com/R4ynXW5.png > > > > Does the placement and the size of that window vary? > > > It does. It uses values persisted to the registry based on the most > > > recent run of the default profile, scoped by the path to the > executable. > > > The registry values can be found at > > > HKEY_CURRENT_USER\SOFTWARE\Mozilla\Firefox\PreXULSkeletonUISettings. > > > > I am running Nightly 86.0a1 (2021-01-07) 64bit on Windows 10 on a freshly > > created profile and checked that the browser.startup.preXulSkeletonUI > > preference is set to true, though instead of seeing the UI I get a blank > > white window. I remember, I tested this feature like a month or two ago > and > > it did work before. Is that expected? If not, please let me know what > > information is needed to track this down and I'll file a bug for it. > > > > Also, regarding the registry values, I only see one for the theme with a > > key referring to the path of the Nightly executable. How will you handle > > different profiles? > > > > Besides those issues, I'm really happy to see this coming. It improves > > perceived start up speed a lot, especially on less powerful machines. > > > > Sebastian > > ___ > > dev-platform mailing list > > dev-platform@lists.mozilla.org > > https://lists.mozilla.org/listinfo/dev-platform > > > ___ > dev-platform mailing list > dev-platform@lists.mozilla.org > https://lists.mozilla.org/listinfo/dev-platform > -- Jared Wein Senior Staff Software Engineer, Firefox Mozilla Corporation ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
dthayer, Congratulations to you and emalysz for getting this enabled in Nightly! I know it's been a long slog, but I think this is going to make a very perceivable improvement to our startup responsiveness. -Mike On Thu, 7 Jan 2021 at 07:20, Sebastian Zartner wrote: > On Wednesday, January 6, 2021 at 10:55:22 PM UTC+1, Doug Thayer wrote: > > On 1/6/2021 1:51 PM, Mike Hommey wrote: > > > > > On Wed, Jan 06, 2021 at 01:46:52PM -0800, Doug Thayer wrote: > > >> On 1/6/2021 1:44 PM, Mike Hommey wrote: > > >> > > >>> On Wed, Jan 06, 2021 at 01:30:00PM -0800, Doug Thayer wrote: > > On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey > wrote: > > > > > On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: > > >> If you don't spend any time on Nightly in Windows 10, please feel > free to > > >> disregard this. > > >> > > >> tl;dr: we're sometimes creating the first window differently than > usual, > > > so > > >> be on the lookout for breakages. > > >> > > >> On 2021-01-05, a change landed in Nightly which enabled the > pre-XUL > > > skeleton > > >> UI [1]. This is a feature which allows us to create the first > window and > > >> populate it with a non-interactive placeholder UI before we load > > > xul.dll. On > > >> some systems, this can mean we can give visual indication of > Firefox > > >> launching as much as 15 seconds sooner than normal (loading > xul.dll can > > > take > > >> a while). We're hoping this could be a big win for users who > experience > > > very > > >> slow startups, and we also hope it will improve the overall > snappiness of > > >> startup even on fast systems. > > > What does the placeholder UI look like? > > > > > Colors and layout can vary, but the basic look is this: > > [image: image.png] > > >>> The image attachment didn't quite work. > > >> Woops. Here is a link: https://i.imgur.com/R4ynXW5.png > > > Does the placement and the size of that window vary? > > It does. It uses values persisted to the registry based on the most > > recent run of the default profile, scoped by the path to the executable. > > The registry values can be found at > > HKEY_CURRENT_USER\SOFTWARE\Mozilla\Firefox\PreXULSkeletonUISettings. > > I am running Nightly 86.0a1 (2021-01-07) 64bit on Windows 10 on a freshly > created profile and checked that the browser.startup.preXulSkeletonUI > preference is set to true, though instead of seeing the UI I get a blank > white window. I remember, I tested this feature like a month or two ago and > it did work before. Is that expected? If not, please let me know what > information is needed to track this down and I'll file a bug for it. > > Also, regarding the registry values, I only see one for the theme with a > key referring to the path of the Nightly executable. How will you handle > different profiles? > > Besides those issues, I'm really happy to see this coming. It improves > perceived start up speed a lot, especially on less powerful machines. > > Sebastian > ___ > dev-platform mailing list > dev-platform@lists.mozilla.org > https://lists.mozilla.org/listinfo/dev-platform > ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
On Wednesday, January 6, 2021 at 10:55:22 PM UTC+1, Doug Thayer wrote: > On 1/6/2021 1:51 PM, Mike Hommey wrote: > > > On Wed, Jan 06, 2021 at 01:46:52PM -0800, Doug Thayer wrote: > >> On 1/6/2021 1:44 PM, Mike Hommey wrote: > >> > >>> On Wed, Jan 06, 2021 at 01:30:00PM -0800, Doug Thayer wrote: > On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey wrote: > > > On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: > >> If you don't spend any time on Nightly in Windows 10, please feel free > >> to > >> disregard this. > >> > >> tl;dr: we're sometimes creating the first window differently than > >> usual, > > so > >> be on the lookout for breakages. > >> > >> On 2021-01-05, a change landed in Nightly which enabled the pre-XUL > > skeleton > >> UI [1]. This is a feature which allows us to create the first window > >> and > >> populate it with a non-interactive placeholder UI before we load > > xul.dll. On > >> some systems, this can mean we can give visual indication of Firefox > >> launching as much as 15 seconds sooner than normal (loading xul.dll > >> can > > take > >> a while). We're hoping this could be a big win for users who > >> experience > > very > >> slow startups, and we also hope it will improve the overall snappiness > >> of > >> startup even on fast systems. > > What does the placeholder UI look like? > > > Colors and layout can vary, but the basic look is this: > [image: image.png] > >>> The image attachment didn't quite work. > >> Woops. Here is a link: https://i.imgur.com/R4ynXW5.png > > Does the placement and the size of that window vary? > It does. It uses values persisted to the registry based on the most > recent run of the default profile, scoped by the path to the executable. > The registry values can be found at > HKEY_CURRENT_USER\SOFTWARE\Mozilla\Firefox\PreXULSkeletonUISettings. I am running Nightly 86.0a1 (2021-01-07) 64bit on Windows 10 on a freshly created profile and checked that the browser.startup.preXulSkeletonUI preference is set to true, though instead of seeing the UI I get a blank white window. I remember, I tested this feature like a month or two ago and it did work before. Is that expected? If not, please let me know what information is needed to track this down and I'll file a bug for it. Also, regarding the registry values, I only see one for the theme with a key referring to the path of the Nightly executable. How will you handle different profiles? Besides those issues, I'm really happy to see this coming. It improves perceived start up speed a lot, especially on less powerful machines. Sebastian ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
On 1/6/2021 1:51 PM, Mike Hommey wrote: On Wed, Jan 06, 2021 at 01:46:52PM -0800, Doug Thayer wrote: On 1/6/2021 1:44 PM, Mike Hommey wrote: On Wed, Jan 06, 2021 at 01:30:00PM -0800, Doug Thayer wrote: On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey wrote: On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: If you don't spend any time on Nightly in Windows 10, please feel free to disregard this. tl;dr: we're sometimes creating the first window differently than usual, so be on the lookout for breakages. On 2021-01-05, a change landed in Nightly which enabled the pre-XUL skeleton UI [1]. This is a feature which allows us to create the first window and populate it with a non-interactive placeholder UI before we load xul.dll. On some systems, this can mean we can give visual indication of Firefox launching as much as 15 seconds sooner than normal (loading xul.dll can take a while). We're hoping this could be a big win for users who experience very slow startups, and we also hope it will improve the overall snappiness of startup even on fast systems. What does the placeholder UI look like? Colors and layout can vary, but the basic look is this: [image: image.png] The image attachment didn't quite work. Woops. Here is a link: https://i.imgur.com/R4ynXW5.png Does the placement and the size of that window vary? It does. It uses values persisted to the registry based on the most recent run of the default profile, scoped by the path to the executable. The registry values can be found at HKEY_CURRENT_USER\SOFTWARE\Mozilla\Firefox\PreXULSkeletonUISettings. ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
On Wed, Jan 06, 2021 at 01:46:52PM -0800, Doug Thayer wrote: > On 1/6/2021 1:44 PM, Mike Hommey wrote: > > > On Wed, Jan 06, 2021 at 01:30:00PM -0800, Doug Thayer wrote: > > > On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey wrote: > > > > > > > On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: > > > > > If you don't spend any time on Nightly in Windows 10, please feel > > > > > free to > > > > > disregard this. > > > > > > > > > > tl;dr: we're sometimes creating the first window differently than > > > > > usual, > > > > so > > > > > be on the lookout for breakages. > > > > > > > > > > On 2021-01-05, a change landed in Nightly which enabled the pre-XUL > > > > skeleton > > > > > UI [1]. This is a feature which allows us to create the first window > > > > > and > > > > > populate it with a non-interactive placeholder UI before we load > > > > xul.dll. On > > > > > some systems, this can mean we can give visual indication of Firefox > > > > > launching as much as 15 seconds sooner than normal (loading xul.dll > > > > > can > > > > take > > > > > a while). We're hoping this could be a big win for users who > > > > > experience > > > > very > > > > > slow startups, and we also hope it will improve the overall > > > > > snappiness of > > > > > startup even on fast systems. > > > > What does the placeholder UI look like? > > > > > > > Colors and layout can vary, but the basic look is this: > > > [image: image.png] > > The image attachment didn't quite work. > > Woops. Here is a link: https://i.imgur.com/R4ynXW5.png Does the placement and the size of that window vary? ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
On 1/6/2021 1:44 PM, Mike Hommey wrote: On Wed, Jan 06, 2021 at 01:30:00PM -0800, Doug Thayer wrote: On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey wrote: On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: If you don't spend any time on Nightly in Windows 10, please feel free to disregard this. tl;dr: we're sometimes creating the first window differently than usual, so be on the lookout for breakages. On 2021-01-05, a change landed in Nightly which enabled the pre-XUL skeleton UI [1]. This is a feature which allows us to create the first window and populate it with a non-interactive placeholder UI before we load xul.dll. On some systems, this can mean we can give visual indication of Firefox launching as much as 15 seconds sooner than normal (loading xul.dll can take a while). We're hoping this could be a big win for users who experience very slow startups, and we also hope it will improve the overall snappiness of startup even on fast systems. What does the placeholder UI look like? Colors and layout can vary, but the basic look is this: [image: image.png] The image attachment didn't quite work. Woops. Here is a link: https://i.imgur.com/R4ynXW5.png ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
On Wed, Jan 06, 2021 at 01:30:00PM -0800, Doug Thayer wrote: > On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey wrote: > > > On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: > > > If you don't spend any time on Nightly in Windows 10, please feel free to > > > disregard this. > > > > > > tl;dr: we're sometimes creating the first window differently than usual, > > so > > > be on the lookout for breakages. > > > > > > On 2021-01-05, a change landed in Nightly which enabled the pre-XUL > > skeleton > > > UI [1]. This is a feature which allows us to create the first window and > > > populate it with a non-interactive placeholder UI before we load > > xul.dll. On > > > some systems, this can mean we can give visual indication of Firefox > > > launching as much as 15 seconds sooner than normal (loading xul.dll can > > take > > > a while). We're hoping this could be a big win for users who experience > > very > > > slow startups, and we also hope it will improve the overall snappiness of > > > startup even on fast systems. > > > > What does the placeholder UI look like? > > > > Colors and layout can vary, but the basic look is this: > [image: image.png] The image attachment didn't quite work. ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
On Wed, Jan 6, 2021 at 1:23 PM Mike Hommey wrote: > On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: > > If you don't spend any time on Nightly in Windows 10, please feel free to > > disregard this. > > > > tl;dr: we're sometimes creating the first window differently than usual, > so > > be on the lookout for breakages. > > > > On 2021-01-05, a change landed in Nightly which enabled the pre-XUL > skeleton > > UI [1]. This is a feature which allows us to create the first window and > > populate it with a non-interactive placeholder UI before we load > xul.dll. On > > some systems, this can mean we can give visual indication of Firefox > > launching as much as 15 seconds sooner than normal (loading xul.dll can > take > > a while). We're hoping this could be a big win for users who experience > very > > slow startups, and we also hope it will improve the overall snappiness of > > startup even on fast systems. > > What does the placeholder UI look like? > Colors and layout can vary, but the basic look is this: [image: image.png] ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: PSA (Windows): Startup Skeleton UI Enabled on Nightly
On Wed, Jan 06, 2021 at 11:57:18AM -0800, Doug Thayer wrote: > If you don't spend any time on Nightly in Windows 10, please feel free to > disregard this. > > tl;dr: we're sometimes creating the first window differently than usual, so > be on the lookout for breakages. > > On 2021-01-05, a change landed in Nightly which enabled the pre-XUL skeleton > UI [1]. This is a feature which allows us to create the first window and > populate it with a non-interactive placeholder UI before we load xul.dll. On > some systems, this can mean we can give visual indication of Firefox > launching as much as 15 seconds sooner than normal (loading xul.dll can take > a while). We're hoping this could be a big win for users who experience very > slow startups, and we also hope it will improve the overall snappiness of > startup even on fast systems. What does the placeholder UI look like? ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
PSA (Windows): Startup Skeleton UI Enabled on Nightly
If you don't spend any time on Nightly in Windows 10, please feel free to disregard this. tl;dr: we're sometimes creating the first window differently than usual, so be on the lookout for breakages. On 2021-01-05, a change landed in Nightly which enabled the pre-XUL skeleton UI [1]. This is a feature which allows us to create the first window and populate it with a non-interactive placeholder UI before we load xul.dll. On some systems, this can mean we can give visual indication of Firefox launching as much as 15 seconds sooner than normal (loading xul.dll can take a while). We're hoping this could be a big win for users who experience very slow startups, and we also hope it will improve the overall snappiness of startup even on fast systems. For a number of reasons, though, getting this to work properly was not trivial. We implement it by creating a window very early in startup [2], and then passing its handle off to nsWindow the first time we would otherwise create the first real browser window [3]. We then would like to treat the window handle exactly as if we had just created it, despite the fact that we did not. Discrepancies arise due to, for example, us having already shown the window, meaning the native events associated with doing so have already come through, and we can't process them to set up our state as we normally would. Accordingly, we do a little dance to try to get our state synced up with how it ought to be if we had just created the window, and we do things a little bit differently when we would normally be showing said window for the first time (because we've actually already shown it). All of this is complexity and things we could get wrong, and it could have consequences on how the window behaves down the line during normal use. For example, in the first iteration of this, we weren't receiving our initial focus event on the browser window, which resulted in the text caret not showing up until closing and reopening the browser [4]. We've done our best to track down and identify all such issues, but it's certainly possible that more could manifest. So please don't hesitate to reach out or file a bug under the meta [5]. Lastly, a big thanks to Emma Malysz who was instrumental in getting this ready to land, to the Windows Widget folks who reviewed it, and to everyone who filed bugs with it during early dogfooding. Cheers, dthayer [1]: https://bugzilla.mozilla.org/show_bug.cgi?id=1680258#c15 [2]: https://searchfox.org/mozilla-central/rev/ef900cd2258d4c5d968093f612f807d96e6e7c98/mozglue/misc/PreXULSkeletonUI.cpp#1933 [3]: https://searchfox.org/mozilla-central/rev/ef900cd2258d4c5d968093f612f807d96e6e7c98/widget/windows/nsWindow.cpp#897 [4]: https://bugzilla.mozilla.org/show_bug.cgi?id=1665456 [5]: https://bugzilla.mozilla.org/show_bug.cgi?id=1665451 ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
