Window Activation

(blog.broulik.de)

142 points | by LorenDB 4 days ago ago

81 comments

  • rs186 5 hours ago ago

    Clicked the article because my blurry eyes read "on Windows Activation", and I was like "huh, what's interesting about Windows activation?"

    Read the first paragraph and it was really confusing. Still the same after reading it again.

    Until I looked at the title. Oh, window activation is what we are actually talking about.

  • dmart 6 hours ago ago

    As a recent Linux (and Wayland) switcher, I love this behavior. It has always felt insane to me that macOS will just let some random auto-updater steal focus and eat your keystrokes while trying to work on something.

    • vbezhenar 6 hours ago ago

      Powerful permissions are needed for powerful apps.

      I don't know about this particular issue, but for example, KiCAD has multiple issues with wayland being overly protective: [0]. For example KiCAD needs the ability to move cursor to provide good user experience. KiCAD needs the ability to move and place windows wherever it likes. KiCAD needs to control focus. KiCAD needs to prevent OpenGL throttling on inactive windows. These issues led KiCAD developers to reduce support for Wayland configurations to a bare minimum.

      So it's a delicate balance for operating systems to both allow powerful apps to implement complicated UI and to prevent badly written apps to do inconvenient things.

      [0]: https://www.kicad.org/blog/2025/06/KiCad-and-Wayland-Support...

      • arghwhat 5 hours ago ago

        s/KiCAD needs/KiCAD wants/

        As a user of KiCAD, I have not found any need for it to automatically move cursors or windows around (nor do I even remember such behaviour pre-wayland, so it can't have been important), but note that the cursor-warp protocol is coming to allow the former, and window tags are coming to allow things like window placement restoration, which should help where this may benefit UX.

        Technical note, OpenGL is for rendering, which is unrelated to presentation. Window managers and display servers have no part in that process. It's the Window System Integration (WSI) if used, such as EGL or Vulkan WSI, and in the old days GLX, that talk to the display server.

        Wayland only provides an optional suggestion for when it is a good time for a window to render for good frame pacing, latency and performance without the app having a full proper frame scheduling implementation itself. The issue that tends to crop up is that EGL, a WSI often used with OpenGL in apps not using a toolkit, when specifically told to block and wait for next frame, has been internally implemented to use the optional suggestion which is not provided for invisible windows.

        Stuff is being done to solve this, and it doesn't affect applications that do not ask to block on updates (say, firefox), nor applications leaving this up to a toolkit (say, Gtk or Qt) or just a different window system integration than EGL (which is extremely limited on its own anyway).

        • vbezhenar 4 hours ago ago

          > As a user of KiCAD, I have not found any need for it to automatically move cursors

          Well, the first thing you do with KiCAD is scrolling to zoom in and out, and KiCAD scroll works in a way to jump cursor to the center, so you basically can pan and scroll at the same time. That's default behaviour unless you changed it in the settings, and, obviously, it needs to warp cursor to the center of the window.

      • jchw 5 hours ago ago

        Unfortunately the KiCAD messaging has been a bit messy. They list a spectrum of issues, some of which are very vague and also clearly issues with KiCAD (like "Application freezes and crashes: Instability issues specific to the Wayland environment" - unless the compositor is crashing I fail to see why you would assume KiCAD crashing is an issue with Wayland or your compositor.) On the other hand I don't really blame application developers for being frustrated in general, because a lot of us have been waiting a really long time to see Wayland issues get resolved, and the pace was so slow until recently that it basically felt like it would take an eternity for anything to get resolved. These days though, the pace is very fast, to the point where almost anything written about Wayland will be out of date in a couple of months, mostly for good reasons.

        > KiCAD needs the ability to move cursor to provide good user experience.

        Most applications are implementing pointer warping using pointer-constraints-unstable-v1. This lets you confine the pointer to a region, at which point you can use relative events to get movement, render the cursor yourself and do whatever you want. There is the locked_pointer_v1::set_cursor_position_hint function to allow one to set the location where the cursor should be released at when the constraint is lifted, which should make everything seamless.

        And sure, it might actually be that pointer-constraints-unstable-v1 isn't enough for KiCAD's particular UX somehow, maybe they need pointer-warp-v1 or something even more advanced. However, applications generally don't need to set the mouse position to arbitrary locations on-screen at any time... That is a useful capability for something doing automation, but it should really not be needed for general application development.

        > KiCAD needs the ability to move and place windows wherever it likes.

        KiCAD isn't a window manager, it's a damn EDA tool. I do agree that Wayland needs to provide multi-window applications with better tools to hint to the compositor what to do with window placement and especially to save and restore window positions, but this doesn't translate to "applications need to be able to decide where exactly windows go." There is basically no behavior which literally requires this, and certainly no sane behavior that requires this.

        Having every application perform its own sort of logic to decide where windows go is a mess everywhere it exists. It would be cleaner and better for users if we could just figure out what sorts of higher level tools applications need for good UX and try to build around that. In most cases merely being able to position windows relative to each-other is enough. (You can obviously do this in Wayland already to some extent, though I'm sure there are missing tools that are needed.)

        On Wayland today, applications can't absolutely control window placement, or even know where they are on screen. There really isn't even a global window coordinate space to even leak to applications. It's a pretty radical departure from almost everything else, so yeah, application developers are obviously not thrilled about having to deal with it. But on the other hand, it's probably the right way to go. Just because ability to control absolute positions is convenient does not mean it is necessarily the right way to go, especially if you can provide higher level tools that encode intent better and let the user decide how your application's intent should be interpreted.

        > KiCAD needs to control focus.

        Honestly I have no clue what they're complaining about with focus. It's too vague.

        If your application is in the foreground, you can grab an activation token and use it, so even with "extreme" focus protection, there should not be any issues with KiCAD being able to focus its own windows.

        As for other software being able to focus itself from KiCAD, well, this article describes how you do it. It's pretty straight-forward and it's not obvious how you would misuse it. Pretty sure the same protocol exists in X11 as well.

        They're also talking about modals, which might be related to their complaints. The xdg-dialog-v1 protocol (supported in KDE 6.4, GNOME 48, and used by Qt 6.8+) gives applications the ability to mark dialogs as modals. It is a bit crazy that it took as long as it did for this to become supported by everything, but it did cross the finish line. On Ubuntu 25.04, for example, you should get GNOME 48 and Qt 6.8.

        > KiCAD needs to prevent OpenGL throttling on inactive windows

        OpenGL isn't throttled, it is stalled if the window is entirely occluded. You can now resolve this issue with the fifo-v1 protocol and Mesa 25.0 or newer. For example, Ubuntu 25.04 ships Mesa 25.x and GNOME 48 which has fifo-v1. fifo-v1 is also available in KDE as of 6.4.

        This should give applications the frame pacing behavior that they want. It is possible to work around the issue to some degree, it's just annoying.

        If KiCAD developers don't want to support Wayland because it's effort they'd rather spend on other shit then fine, XWayland should mostly continue to work as-expected anyways. Best option for now is to force KiCAD to use X11, like Krita does. I'm sure that's not a 100% panacea but it should be good enough especially if KiCAD is so buggy on Wayland that it actively crashes.

      • gf000 an hour ago ago

        They are free to create new protocols (or use existing ones) that allow these higher privileged functionality. Then the server implementation will hopefully figure out a decent way to request that permission and the app can then have it.

        (Though this permission may be display server-dependent, as it may not make sense in case of each).

      • nottorp 6 hours ago ago

        > KiCAD needs to control focus.

        I don't know what KiCAD is, but it certainly does not need to control focus OS wide. Only between its own windows.

        It's probably not KiCAD's fault that the windowing system doesn't work like that, but still...

        • suspended_state 5 hours ago ago

          The page states:

          > Unpredictable window focus behavior that can interrupt workflows

          Which isn't exactly the same issue, so indeed it doesn't need to control focus.

          • nottorp 5 hours ago ago

            That sounds like my problem with focus being stolen by random apps while i work :)

    • bityard 34 minutes ago ago

      I have either approved or denied about a dozen things on my MacOS work laptop and have no idea what they were because I was in the middle of typing a sentence and happened to hit the spacebar when the dialog popped up. Hope none of them were too important!

    • mayoff 4 hours ago ago

      Supposedly this was improved in macOS 14 (Sonoma, late 2023) with "cooperative app activation". It's discussed in this WWDC 2023 video:

      https://developer.apple.com/videos/play/wwdc2023/10054/?time...

      • xp84 4 hours ago ago

        Since it's usually Apple's own OS stuff usually to blame with their incessant "GIVE ME YOUR PASSWORD... something something updates" dialogs, I won't hold my breath.

    • Defletter 4 hours ago ago

      Yup. I used to use a Macbook Pro as my daily driver and played League of Legends on it... and the amount of forced-focus was infuriating. You just locked in and are messaging your friend on Discord about something? Well, there's 10 seconds left until the game starts and that's more important so you're focusing the League client now.

    • dataflow 5 hours ago ago

      > It has always felt insane to me that macOS and Windows will both just let some random auto-updater steal focus and eat your keystrokes while trying to work on something.

      Wait, what? Hasn't Windows prevented focus stealing for literally decades at this point?

      https://devblogs.microsoft.com/oldnewthing/20090220-00/?p=19...

      • ack_complete 3 hours ago ago

        It used to block focus stealing aggressively unless a program had foreground permission or was given it (AllowSetForegroundWindow), but the mechanism seems broken in current versions of Windows.

      • jenscow 5 hours ago ago

        An app can still steal focus with `uiAccess=true` in the app manifest's execution level (and the app is signed).

      • dmart 5 hours ago ago

        Ah, that may be the case - I’ll edit my comment. I was primarily using macOS before this so I may have misremembered the Windows behavior.

    • anonym29 6 hours ago ago

      >It has always felt insane to me that macOS and Windows will both just let some random auto-updater steal focus and eat your keystrokes while trying to work on something

      What's so crazy about that? Windows and Mac OS are already functionally spyware posing as operating systems, as Microsoft and Apple are functionally intelligence agency partners posing as private corporations.

      • Pesthuf 4 hours ago ago

        …if that was the reason, why would the operating systems give other applications the right to steal focus and record keystrokes? They control the kernel, they don’t need that.

        • anonym29 4 hours ago ago

          Habituate and condition users to abuse and lack of control. No pressure for OS developers to respect the agency of their users.

          • SkiFire13 2 hours ago ago

            > Habituate and condition users to abuse and lack of control

            We could say the same about X11, no?

      • eddythompson80 5 hours ago ago

        Wait, you can do that in X11 too... Is X11 spyware??? I know there is xeyes.. Is it..

        • anonym29 4 hours ago ago

          In the past, I would've said no. It absolutely had severe vulnerabilities, no question about it. Anything in userland monitoring keystrokes, mouse input, and display of anything else is userland is genuinely concerning; that said, these were byproducts of architectural decisions made long ago in open source software - not quite the same as deliberately writing code explicitly and specifically to take away privacy and control from your users the way Microsoft and Apple do.

          These days however, the negligence of the current custodian, Red Hat, does seem to border on malicious, especially when forks like XLibre are continuing to patch vulnerabilities while Red Hat refuses to merge patches into the "official" X11, as part of a coercive strategy of trying to force all users onto Wayland by allowing X11 to become even worse through active refusal and neglect to merge good PR's with security patches, despite being the official project owner and custodian.

          As a final note, I did not say that Windows and Mac OS were spyware, I said they were functionally spyware. There's a meaningful and nuanced difference between those two claims that I'm not sure you are discerning in accordance with my intent.

          • eddythompson80 3 hours ago ago

            I don't know man. I think there is a much simpler explanation than the crazy fan fic your writing there.

            • anonym29 3 hours ago ago

              Can you be more specific about what parts of my perspective appear crazy, or fan-fic to you? There is heaps of well-documented evidence from reputable sources to support all of my claims that I would be eager to offer. What specific claims do you find dubious?

  • nh2 7 hours ago ago

    This mechanism sounds worth it.

    So many times on X11 do I type some chat message, and then some popup from another program comes up, which I accidentally confirm by my typing containing a space which presses the confirmation button, and I don't even know what the popup was.

    Or my password being typed in a popup.

    I once patched some code into i3 to prevent this for myself, but it wasn't a clean solution.

    • eqvinox 2 hours ago ago

      KDE: Settings → Window Management → Window Behavior → Focus → Focus stealing prevention

      Even on "Low" (the options are None, Low, Medium, High, Extreme) I'm not seeing this behavior. Might be an i3 problem.

  • nottorp 6 hours ago ago

    I don't understand who historically has thought it's a good idea to allow applications to steal focus in the first place. It should be the window manager's decision, and the window manager should only switch focus if the user decides that.

    • SoftTalker 11 minutes ago ago

      You think that's bad, back in the day when I was in an office where everyone used X terminals off of a common unix server, you could open a window on someone else's screen by just changing your DISPLAY environment variable. Fun pranks were fairly common.

    • guardian5x 6 hours ago ago

      Well, sometimes the user expects the focus to shift, like the example mentioned when you click a link in one application and your browser in the background should come into focus when it opens a new tab. Some applications just decide to steal focus when the user does not expect it, and that is the problem.

      • somat 3 minutes ago ago

        I am not sure, as a convert to the church of "focus follows mouse" I sort of want well... my focus to follow the mouse and the mouse to follow me.

        Now there may be a legitimate case to steal focus, but I am unable to think of one at the moments and your click link example fails to convince me.

        I also sort of hate modal dialogs/windows. I think modals are in general an indicator of lazy/bad design. That being said, there are legitimate cases for modals. but "stop the world and handle me" should be a last resort not the first.

      • BobaFloutist 3 hours ago ago

        If you click a link in one application, surely it should pass focus to the browser, why should the browser be initiating that process?

        • watusername an hour ago ago

          Only the invoked app knows whether it needs the focus in the first place. Maybe the link you clicked is supposed to initiate some background processing that does not demand your focus at all.

          • BobaFloutist 10 minutes ago ago

            Sure, so the previous app can give the option to take focus to the browser which can take it or not as it wishes.

      • nottorp 6 hours ago ago

        Yes but there's no way for the OS to know if the focus request is legitimate, is there?

        Can't even say "browsers are allowed to grab focus" because they'll grab it for a stupid window telling you to update the browser or what new features no one cares about they introduced.

        I'd prefer to have to switch focus to the browser manually than have the stupid ubuntu update manager steal focus when i'm typing in the terminal...

        • elehack 5 hours ago ago

          The article is about a mechanism for the OS to validate focus requests. The application with the link requests a focus token, and passes it to the browser along with the open-link request, and the browser can then request focus.

          It isn't perfect, because there's no way to know that the browser isn't using the token to request focus for something else, but maintaining and validating chain of custody for focus across applications is exactly the problem it looks like they are working on solving.

          • xp84 3 hours ago ago

            That was exactly the example given in the article, but somehow this isn't what I expected would happen if I click a link in say, my email client or chat program.

            I imagined it more like: User clicks link in email program. Email program tells OS: "Here, open https://..." -- OS checks URL scheme registry and selects Firefox, OS brings Firefox to the front and throws the URL at it and says "Open this."

            I guess perhaps my naïve way could falls down if the OS accepts URLs from apps that aren't in the foreground, so a random background process could activate any app it wants to steal focus.

            • elehack 2 hours ago ago

              Yep. With the solution discussed, as I understand it, the e-mail program just needs to be modified to request a focus token and send it along with the URL request to the browser or the OS browser dispatch service to keep the expected behavior.

              This could be abstracted by libraries (e.g. a method in Qt to open a URL in the system browser automatically gets the token) so each application doesn't need to be updated separately, or possibly even OS services.

        • Ukv 5 hours ago ago

          > Yes but there's no way for the OS to know if the focus request is legitimate, is there? Can't even say "browsers are allowed to grab focus" because [...]

          To my understanding, the approach described in the article is that the currently active program requests a token and then passes that along to the program that it wants to take focus. Compositor can also check what triggered the request (mouse click? global keybind?) to decide if the request is legitimate.

          That seems reasonable to me, opposed to requiring the user to switch over to a new window every time they `right click -> show in file browser` a file in their IDE, or after they press a hotkey to open a screenshot tool, or so on.

          • nottorp 4 hours ago ago

            > Compositor can also check what triggered the request (mouse click? global keybind?) to decide if the request is legitimate.

            That's what I'm dubious about. But I haven't look at the details ofc.

    • eqvinox 2 hours ago ago

      KDE has KWin settings controlling this. I have no idea if this is some kind of a fixup after the fact or whether the window manager always controls this, but at least it does on a KDE X11 session.

  • sho_hn 6 hours ago ago

    Earlier discussion with comments from devs https://news.ycombinator.com/item?id=44784312

  • eqvinox 2 hours ago ago

    > Well, you probably know by now that Wayland, unlike X, doesn’t let one application force its idiot wishes on everyone else.

    …I thought {not allowing,managing} this on X11 is the window manager's job? (kwin certainly doesn't allow it on my X11 session…)

    Or is this arguing about "uncooperative"/"hostile" applications?

  • treve 5 hours ago ago

    Great idea, but pretty painful at the moment. I guess not everything uses this protocol yet, so I often can't find (for example) my password pops under other windows. Hoping this gets a bit better over time, it's one of the last remaining Wayland pains.

  • wronex 4 hours ago ago

    Wait, hold on. Is this actually an issue that needs a solution? It feels like Wayland is doing something very stupid here. Why not let apps control their windows? I cannot remember when an app stole focus last time. The only time this makes sense is while entering a password. But that is a very specific case that can be solved by having the password dialog on a protected desktop (ie. one with only that single window.)

  • imchillyb 34 minutes ago ago

    The power of a system does not lie within its mechanisms, systems, and strategies.

    The power of a system allows one -near infinite- ability to create and manipulate those mechanisms, systems, and strategies.

    The most powerful systems have few safeguards or rails, and user beware.

    The most restrictive systems we hand to grandma and grandpa, knowing there is little they can actually do with them.

  • burnt-resistor 6 hours ago ago

    I can only barely appreciate or fathom the endless masochistic self-abuse of maintaining functional, useful semi-headless UI automation testing for various Linux distros.

    • OsrsNeedsf2P 3 hours ago ago

      If you did have UI automation, you probably would do it at the DE level, and not swap things like X11 for Wayland. If you don't update (or use something like XFCE), it would probably remain functional for decades

  • webdevver 6 hours ago ago

    the pragmatic thing to do is just let the Free Market decide. as far as i understand, windows just lets apps grab whatever window they want, whatever input they want, right? and everything Just Works(tm). app writers are discouraged to make things too clever by virtue of users having the choice of not using the app in question.

    why cant linux guys just... copy windows?

    android-ifying this space with permissions, channels, protocols etc, and pretending that apps are insecure is adding friction that benefits nobody imo.

    • LorenDB 6 hours ago ago

      Sometimes I type a password into one window, only to have another window pop up partway through and eat the rest of my input. This is why we need to prevent unintentional window activation.

      • bloomca 5 hours ago ago

        It is relatively easy to replicate if you open 2 apps and start typing in the first one which opened, both on macOS and Windows (I don't use Linux enough to notice this issue).

        A proper solution is probably faster startup times, but overall it pretty much never happens? Idk maybe I'm lucky or just conditioned to ignore it.

      • Linkd 6 hours ago ago

        This happens so rarely, that it makes the UX impact to the every day user not worth it in my opinion.

        • Barbing 5 hours ago ago

          Fellow macOS users: is this rare for you as well?

          Maybe an auto-updater will do this, and if it happened with any frequency I might disable those autoupdates and try a macro-based (e.g. Keyboard Maestro) solution.

        • LandR 4 hours ago ago

          Windows stealing focus happens to me multiple times a day on Windows when I'm working.

          It's infuriating.

    • j1elo 6 hours ago ago

      > windows just lets apps grab whatever window they want [...] and everything Just Works

      Not really, as proven by the amount of searches with "Windows 11 disable focus stealing" (and ensuing frustration after seeing that it's not a simple toggle somewhere in the Settings) that I've done over time, and confirmed with so many coworkers over the years that we'd like to disable it.

      Windows in particular and computers in general, work as they do, and people just adapt to it and sigh in frustration, assuming that things must be that way and there's nothing that can be done to change it. It's difficult to measure "Just Works" if there are no satisfaction surveys for each feature (also would be impractical). Focus stealing in particular is so ingrained in people's minds that I doubt many are even aware that it could work differently.

    • mathiaspoint 6 hours ago ago

      It already works that way on X11.

      Linux is already set up to handle this better than Windows actually since most apps are open source and abusive window management is likely to result in PRs.

      • pjmlp 6 hours ago ago

        Someone has to actually accept and merge them.

        • mathiaspoint 6 hours ago ago

          Not necessarily. The fork could get packaged instead if the users prefer it.

          • pjmlp 6 hours ago ago

            As history has proven multiple times, most forks fail, after those that made them in first place lose interest keeping up with upstream, while others appreciate the fork as long as they aren't the ones actually doing the work.

            • pxc 5 hours ago ago

              You're right, but it's not unusual for distro maintainers to carry patches for one or two removing an obnoxious behaviors for a long time.

  • jovial_cavalier 5 hours ago ago

    Stealing focus is possible in X11, but the window manager needs to implement it. For instance, my dwm build does not refocus for any reason other than the user moving the mouse or pressing a key

  • andrewmcwatters 5 hours ago ago

    It's not just windows that I love popping up in my face actively! interrupting what I'm doing, but also ones that have autofocus elements, doubly stealing my attention and not having a debounce for ignoring actions, as others here have mentioned.

    Type-type-type...HEY THIS APPLICATION HAS SOME UPDATES HERES A CHANGEL-keypress closes window

    I wanted to read that, damn it!

  • zb3 7 hours ago ago

    Umm.. thanks to this logic I had to write an extension just so I could open firefox using a keystroke, because otherwise the browser did not receive focus..

    • antnisp 6 hours ago ago

      I just checked and assigning the shortcut in "System Settings>Keyboard>Shortcuts" will open Firefox and put it in focus.

      • zb3 6 hours ago ago

        For me in GNOME on Fedora this only works for chromium, for firefox I had to make an extension - I don't know why.

    • wilkystyle 7 hours ago ago

      Trade-offs abound, but this sounds amazing to me. I already have hotkeys to instantly switch between browser/terminal/Emacs/etc., so it's not an issue for me. What is an issue is some other application stealing focus while I'm typing elsewhere and (as another commenter mentioned) accidentally pressing space or some other key that performs an action in whatever pop-up or application stole the focus.

      • johnisgood 6 hours ago ago

        You should have focused more! /s /pun intended

        But yeah, it has happened to me too, too often for it to be a problem. Especially the press the space bit.

        I am not sure this is the right solution, however, but I cannot think of any solution right now.

        Someone (in the comments) who has claimed to patch i3 may shed some light on what he did.

  • rekabis 5 hours ago ago

    This title seems click-baity, as the term is most frequently used for registering Windows. That was my curiosity when I clicked through. I somehow doubt it would have gotten as many clicks had it been “Window Focus”.

    • sho_hn 2 hours ago ago

      It's called window activation in the standard protocol the blog is about, so it's technically correct terminology.

    • OsrsNeedsf2P 3 hours ago ago

      I don't think Linux users, much less Linux desktop developers, are thinking about Windows license activation.