Some windows sometimes not showing

[alt-tab-macos-bot]

This issue was opened by a bot after a user submitted feedback through the in-app form.

Message:

and sometimes applications may disappear from the alt-tab for no reason (e.g. Zoom, one of the opened pdf)

I just changed my os from windows to mac and I found mac os SUCKS

[lwouis]

Can you please provide more information? A video and steps to reproduced would help a lot

[newtohere-ui]

Can you please provide more information? A video and steps to reproduced would help a lot

This is what I am talking about, the "Preview" app from apple disappeared from the alt-tab

[lwouis]

Does it happen with only Preview, or other apps? Does it happen often, rarely? Does it happen in particular scenarios like when you start the computer, when you plug in an external monitor, etc?

What would really help is steps to reproduce the issue, otherwise it's really hard to know what's wrong on your particular machine, since this issue doesn't happen on mine, and doesn't seem to happen to other people as far it seems.

[newtohere-ui]

Does it happen with only Preview, or other apps? Does it happen often, rarely? Does it happen in particular scenarios like when you start the computer, when you plug in an external monitor, etc?

What would really help is steps to reproduce the issue, otherwise it's really hard to know what's wrong on your particular machine, since this issue doesn't happen on mine, and doesn't seem to happen to other people as far it seems.

This issue happened in Preview and Zoom so far. Though the issue does not happened very often, it could be confusing and only close and re-open the application will help. Also, this issue seems to happen to a particular window but not the whole application. i.e. If I opened A.pdf and B.pdf with Preview and when A.pdf is disappearing from AltTab, B.pdf could be still shown on alt-tab and works normally.

"Does it happen in particular scenarios like when you start the computer" I don't think so, it seems to be a random occurrence. "when you plug in an external monitor" I don't have an external monitor.

I don't have an idea to reproduce the issue at the moment.

[lwouis]

Are you fullscreening these windows perhaps? There are known issues with fullscreening windows making them disapear (for complex reasons)

…

On Sat, Oct 10, 2020 at 14:49 newtohere-ui ***@***.***> wrote: Does it happen with only Preview, or other apps? Does it happen often, rarely? Does it happen in particular scenarios like when you start the computer, when you plug in an external monitor, etc? What would really help is steps to reproduce the issue, otherwise it's really hard to know what's wrong on your particular machine, since this issue doesn't happen on mine, and doesn't seem to happen to other people as far it seems. This issue happened in Preview and Zoom so far. Though the issue does not happened very often, it could be confusing and only close and re-open the application will help. Also, this issue seems to happen to a particular window but not the whole application. i.e. If I opened A.pdf and B.pdf with Preview and when A.pdf is disappearing from alt-tab, B.pdf could be still shown on alt-tab and works normally. "Does it happen in particular scenarios like when you start the computer" I don't think so, it seems to be a random occurrence. "when you plug in an external monitor" I don't have an external monitor. I don't have an idea to reproduce the issue at the moment. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#639 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAZ5U2A4LQAKR4I35S25DLSJ7YWPANCNFSM4SG7ARYQ> .

[newtohere-ui]

Are you fullscreening these windows perhaps? There are known issues with fullscreening windows making them disapear (for complex reasons)
…
This

No, I am not fullscreening these windows, unfortunately.
This issue has just happened to me once again, this time is safari (I am so sorry......), but I still have no idea how to reproduce it.

[lwouis]

Based on what you said, that it's window-specific and not app-wide, and that it happens randomly, my best guess it's that it's the tab detection code triggering incorrectly. This is the same issue that's probably the root cause of #603. This tab detection code has issues with fullscreen'ed windows, or general interactions with other Spaces (fullscreen windows are on dedicated Spaces actually). Do you have multiple Spaces? Do you move windows from one to another?

In the Preview screenshot above, could you retrace the history of that window? You created it by double-clicking a file in Finder? Or maybe you opened Preview and it restored this window from last time you quit it? Or maybe you restarted your computer and it restored Preview as well as this window since it was open before the restart? I'm trying to understand the exact scenario of how the window was created.

Then once created, was it visible in AltTab at this point? Then before you took the screenshot, did you minimize, hide, move Space the window?

What about AltTab itself, was it started the whole time, before you opened the Preview window, or did you start it at some point later? When exactly?

I hope it's not too many questions for you. I'm trying to analyze and imagine what could be at play here since I know the implementation interact differently depending on all the things I just listed

[lwouis]

@newtohere-ui could you please check out my previous message?

[newtohere-ui]

I never use multiple Spaces. I created it by double-clicking the file in Finder. I close everything after finishing my work, leaving no cache and shut down the computer.

It is visible in AltTab when I open the document (safari and zoom do the same) and sudden disappears afterward. Before I take the screenshot, I didn't minimize, hide, move Space the window.

AltTab is set to start when login and it run the whole time

[koenlek]

I have this issue as well. I mainly noticed it with my VS Code windows disappearing from my configured shortcut 1.

My setup:
MacOS 10.15.7 on Macbook pro 13 with a 27 in external monitor. AltTab 6.12.0 with settings:


MacOS mission control settings:

The issue happens on both monitors. Both monitors have a mix of full screen apps and main space apps. A typical mix of apps I have opened is: 1 iTerm2, multiple VS Code windows, 1 full screen chrome, 1 full screen slack.

This happens to me on a daily basis. It only seems to happen with shortcut 1 (see screenshot). shortcut 2 seems to work fine (I use cmd+tab to go to VS Code, then alt+` to rotate between windows of VS Code on the current monitor.

Restarting AltTab fixes the issue (but usually it's back within the same day). I haven't figured out a way yet to reliably reproduce the issue though.

As restarting AltTab helps, I was thinking you could perhaps make a scheduled function that does the initialization part in a sandboxed call to determine the set of all windows and checks for mismatches between that init and whatever AltTab currently thought the set of windows are. If there is a mismatch, you've detected a bug. You can reset the set of windows and collect some diagnostic information which you could prompt the user to ask for permission if it could be shared.

The scheduled function could run every 15 minutes or so, or ideally, make it configurable as I'd like it at 1 min or so as this issue bothers me so frequently.

[koenlek]

I can confirm the same issue also happens with iTerm2.

For completeness, here are my Appearance settings:

@lwouis, any ideas? I really think this is a great app, but it is currently way too buggy for me :(. Perhaps it's due to my setup/settings, which I'm happy to adjust if that could help.

[lwouis]

@koenlek the issue described in this ticket never happens on my machine, thus i can't reproduce and understand what's at play.

Steps to reproduce would really help move this ticket forwards as i would be able to witness the issue and debug it.

[koenlek]

Unfortunately I haven’t been able to find a pattern that reproduces it. I just know it happens multiple times a day for me. I noticed it most with VS Code and iTerm2, because they are my most used apps. I’m not sure if they are actually more sensitive to this issue, or if I just notice it much more with those apps.

Would you be willing to try and run you system with the same settings as I have (see screenshots above) and see if you ever run into this issue?

From my side, I’ll do some more testing to see if I can further narrow down the issue. I’m probably going to set my preferences to default and if that solves it, go step-by-step towards my current preferences.

Also, as said, closing and reopening the app solves it, so it should be possible to write a monitor that fakes app initialization at a regular interval, to detect any mismatches in the existing windows bookkeeping and a fresh init of it. Does that approach makes sense?

But first I guess we need to be more clear om how many people are affected by this. Based on this ticket there are already two people that took the effort of reporting it.

[bmurphy1976]

I still run into this once or twice a week and it's almost always a Sublime Text window.

I'm a very heavy user of multiple works spaces and I'm constantly jumping from workspace to workspace using the keyboard. I typically have multiple iTerm windows open and I'm very frequently opening and closing sublime and visual studio code sessions from the command line.

I suspect this heavy churn is part of the problem, but I can never reproduce it when it happens.

Related, I had an instance this week where Alt-Tab was remembering a window that was recently closed. I had to restart AltTab to fix that. This seems like a similar problem, instead of missing the window open event, Alt-Tab seems to have missed the window closed event.

[koenlek]

@lwouis, is there any way I can reset my preferences to defaults? Maybe some config file I could delete or some plist reset command? I was trying to go back to defaults but I couldn't find a way to know what the actual defaults are ;)

[lwouis]

@koenlek yes, AltTab is using the system-wide preferences system. This means that you can delete all the preferences you have set using the defaults program shipped in macOS:

defaults delete com.lwouis.alt-tab-macos

You could also reset individual settings (e.g. "hideThumbnails" here):

defaults delete com.lwouis.alt-tab-macos hideThumbnails

The same program can reset preferences in any app that uses the system-wide preferences system

Also, as said, closing and reopening the app solves it, so it should be possible to write a monitor that fakes app initialization at a regular interval, to detect any mismatches in the existing windows bookkeeping and a fresh init of it. Does that approach makes sense?

The way the app re-detect existing open windows at launch is really messy. It uses private APIs to bring all windows into the current Space, observes them, then sends them back to their original Space. This can create a visual flash on some slower machines. It's hacky, brittle, and certainly not something that should be done on a schedule. See #447 for more explanations on what we are currently doing, and other workarounds (the lack of public APIs) we are discussing.

But first I guess we need to be more clear om how many people are affected by this. Based on this ticket there are already two people that took the effort of reporting it.

I have decided against any form of analytics/telemetry from AltTab. The app is not spying on users in any capacity. This unfortunately means that I'm in the dark regarding usage in the wild. There is a feedback form built-in the app, and people can also come to Github directly (usually only the technical fraction of users). People can also elect to send a crash report on crashes, but in our case here there is no crash. In short, the 2 users in this ticket are all we have so far to figure out how to reproduce the issue consistently , so it can be fixed.

[lwouis]

@bmurphy1976

I'm very frequently opening and closing sublime and visual studio code sessions from the command line.

How exactly do you do that?

AltTab subscribed to the Accessibility API on the open apps. Then it gets info that windows are opened or closed in that app. If you click on the Dock to quit an app, close a window with the mouse on the red cross, etc, it triggers the Accessibility event and AltTab updates consequently. It seems that maybe the unusual way you use to close/quit things may make it so no event is sent to AltTab. Are the windows fullscreen sometimes when you close them, or quit the app?

@bmurphy1976 @koenlek fullscreen windows is the number 1 scenario I would suspect to cause issues since a fullscreen window on macOS is a window that exists in its own Space, creating all sorts of trouble for AltTab since a window on another Space requires use of private APIs and hacks. (There is no public API to know what's on another Space)

[bmurphy1976]

@lwouis I have to frequently bounce between multiple work spaces throughout my day. I use command line commands such as code . (Visual Studio Code) to open up editor windows as I'm moving around the command line and exit the app when done (usually command-q). I do the same thing with Sublime Text and also usually have multiple browsers and terminal sessions open at the same time to organize the work.

I also heavily use "OSX Workspaces" and switch between them using keyboard shortcuts (^1 through ^6). ^1 is primary, ^2 is slack, ^3 is email, ^4 is secondary workspace, ^5 is music, ^6 is other.

So I'm constantly bouncing around the workspaces, opening closing windows, tabs, editors, browsers, etc. That's what I mean by a lot of churn and why I need a tool like AltTab, the built in application switcher doesn't cut it.

Add in frequent zooms, occasionally going full screen in various apps, using BetterTouchTool keyboard short cuts to constantly move windows around and moving windows between workspaces (sometimes with keyboard, sometimes drag/drop via expose). You can see why I may have a higher probability of triggering the bug but also a hard time reproducing it.

I'll try paying more attention to how and when I'm quitting apps (especially when full screen) to see if there's something there. I usually see it with Sublime Text which I don't go full screen very often, but I do open/close and move between workspaces a lot.

[koenlek]

I tried with default settings for about a week and didn't have any problems! I'll now start changing settings in batches to try to find which setting was causing my issues :)

[OptimusPrime-GIF]

I have the same issue, but with fullscreen windows. It happens randomly. Yes, showing every space is on.

[superlevure]

I have the exact same issue, it happens more often with VSCode, sometimes AltTab will show only one of the several VSCode windows, sometimes none. It also happens with Alacritty

Unfortunately I haven't been able to find a pattern that reproduce the bug, but it happens several times a day.
Restarting AltTab seems to solve the issue temporarily, I can provide a video if that's of any help for you folks

Here's my config:
AltTab Version 6.12.0
MacOS: Catalina 10.15.7

In any case, thanks for the great software !

[lwouis]

@StFS thanks for the nice report. I have a few questions to try and imagine what could be going wrong:

• How do you unplug you external monitor? You unplug, then close your laptop lid to put it to sleep, or do you maybe put to sleep first by closing the lid, then unplug the monitor? Could you maybe play with both to see if one triggers the issue more than the other?
• What are your AltTab preferences? Especially the Appearance tab.
• You put the laptop to sleep right, you don't log out of your session? I'm asking cause these are 2 very different things. Sleep means RAM is sent to disk, then back to RAM on wake. It's a pure stop/resume. Log out quits all apps. But then macOS these days has this feature where it can restore the previously open apps and windows. Both look very similar, but technically are completely different. You're not login out of your session are you?
• Are you sure AltTab is continuously running between at work, then at home? It's not quit or crashed between travel or when you open the laptop at home, is it?

[StFS]

Sorry for the delay in answering. I will include some answers inline although they may be a bit incomplete.

However, I did discover one thing in my settings that I have now changed. I noticed that I had Show Windows from: Screen showing AltTab in my settings. I have now changed it to All Windows.

I do believe that if you have the "screen showing AltTab" configured, if you have some windows on different screens and then you unplug the external screen, AltTab will not pick up on the change even though MacOS does move the windows that were on your external monitor over to the laptop screen.

This is an issue, but I believe it should not be mixed in with this issue.

However, I'm not quite sure anymore whether I have experienced this issue or whether I was just noticing windows missing that were on the external monitor when I left work.

So I think the answers below are irrelevant now, but I'll answer them anyway.

• How do you unplug you external monitor? You unplug, then close your laptop lid to put it to sleep, or do you maybe put to sleep first by closing the lid, then unplug the monitor? Could you maybe play with both to see if one triggers the issue more than the other?

I probably do both. I'm not at work these days but I can try doing some experiments with my setup here at home with an external monitor. Will report back if I find something definitive.

• What are your AltTab preferences? Especially the Appearance tab.

But please note my answer above. I believe what I was experiencing did have something to do with the settings... but not the Appearances settings, but rather the "Show windows from: Screen showing AltTab" in the "Controls" settings pane. Which I have now changed to "Show windows from: All screens".

• You put the laptop to sleep right, you don't log out of your session? I'm asking cause these are 2 very different things. Sleep means RAM is sent to disk, then back to RAM on wake. It's a pure stop/resume. Log out quits all apps. But then macOS these days has this feature where it can restore the previously open apps and windows. Both look very similar, but technically are completely different. You're not login out of your session are you?

I'm not logging out. Just putting the laptop to sleep.

• Are you sure AltTab is continuously running between at work, then at home? It's not quit or crashed between travel or when you open the laptop at home, is it?

Yes, AltTab continues to run once I open my laptop back up. No crash.

[lwouis]

Hopefully fixed/improved in v6.32.0

[bellerofonte]

Hi! I have the latest AltTab version 6.33 installed on my macOS 12.3.
The issue is constantly reproduces at random moments.
The moments I have noticed:

• only secondary workspace affected
• reproduces after sleep/wake
• only reboot fixes the issue (neither restarting AltTab nor re-creating workspace helps)
• the windows that have fallen out of AltTab on one workspace aren't shown on another if (I manually drag it between workspaces)

UPD: steps to fix without reboot:

1. quit AltTab
2. drag all windows to the main workspace
3. close (delete) the workspace which had the issue
4. do some native Cmd+Tab between affected and not affected windows
5. create new workspace and drag all required windows back to it.
6. start AltTab

And yes, it is sometimes much easier to reboot...

[erikaellr]

This started happening to me in 6.46.1, with macOS 12.3, but only after I moved to a new machine - I'd never seen it on my previous macbook in the 2 years that I used AltTab with it (my old macbook is also currently on 6.46.1, and macOS 12.4), but now I see it randomly maybe once a day, one or more windows (as many as three at a time) will just disappear. Toggling between "all screens" and "screen showing AltTab" as one user reported fixing it, didn't seem to make a difference for me. So far, just quitting AltTab and restarting it has fixed it until the next time it randomly happens.

[lwouis]

@erikaellr most likely #1324

[truongnmt]

I'm on Mac 12.2, M1 Pro. My Zoom did not appear previously but restarting AltTab fixed it. FYI

[SudipSinha]

I have been getting this issue randomly on my MacBook Pro (M1 Pro) with MacOS Monterey (version 12.5.1). Usually I don't see my Slack window, but today it was Chrome and VSCode. I haven't been able to replicate the issue, but restarting AltTab seems to resolve the issue, at least temporarily. That's all until I find anything useful/replicable, but just thought of putting this out there.

[truongnmt]

Just an update (Mac 12.5, M1 Pro), I "feel" it less happens after I hide the window thumbnails.

Preferences > Appearance > Hide window thumbnails

[austingayler]

Same, simply restarting fixed it.

[anibal]

I had a very specific case involving Zoom windows not being shown, restarting fixed it. I'm on version 6.46.1 on macOS 12.0.1

[lekseven]

Telegram is always at the end of the AltTab list. If I close AltTab and get back to the default MacOS switcher, Telegram shows up with no window at first. Then I do Command+O, the Telegram window finally shows up and everything seems to be fine with the default switcher. But when I come back to the AltTab switcher the issue is still there. Same with Zoom.

[lwouis]

@lekseven please see #2096

[jindradev]

The issue still persists.
I have no reproduction steps to report and honestly doubt anyone will, I advise adding an option to record some sensible logging for later submission.

[andyborrell]

Happens to me daily on version 6.53.0. Usually vscode, it's not full screen or minimized. Seems to be related to unplugging external monitors. I'm using DisplayLink to connect monitors.
Restarting AltTab does not fix the issue. It usually isn't fixed until the external monitors are reconnected.
Unfortunately it makes AltTab unusable for me.

[lwouis]

@andyborrell i think you're experiencing #1324

[occludedpixel]

I am having an issue with Qoppa PDF Studio.

The app doesn't show up if it is launched when AltTab is already running and I have to restart AltTab for the app to show up. There is also the same issue if the app is running but does not have any windows and I open a file (creating a new window) while AltTab is already running.

Additionally, even when the app shows up in AltTab, its app icon isn't displayed properly as shown below:

I have also noticed that I can at least get the app to show up but without the preview if I move to another space and trigger AltTab as shown below:

In this situation, the app always remains at the end of the list in AltTab instead of moving to the front whenever I focus the app.

I am running:
AltTab Version 6.67.0
macOS 14.1.1 (23B81)

[lwouis]

Hi @occludedpixel,

I downloaded this app and used the free trial to investigate. This is a typical case of a ported app. The installer was a Java installer, so I assume this is cross-platform Java app.

As is common with these type of apps, it has plenty of issues on macOS. The windows are incorrectly programmed, thus AltTab has issues reporting them. It's not just AltTab though. Any accessibility app will have issues with this app.

The only possible fix is on the side of this app creator. I suggest you contact their support since this is a commercial app, and share the issue with them.

Thank you 🙇‍♂️

[valentinvogt]

I have the same issue with the "Preview" app which is reproducible on my machine:

1. Start AltTab
2. Open "Preview"
3. Close all currently open PDFs
4. Open several PDFs at once
   

Then, not all PDF Windows are shown by AltTab.
Sonoma 14.4, AltTab Version 6.67.0

[beeblebrox3]

This problem is happening with me too like twice a week. Restarting alttab solves the problem. The only app affected by it is arc browser. I was exploring the settings today and found out that if I set the value "show" to "Fullscreen windows" Arc starts to show up again. But Arc isn't fullscreen at the moment.