Actually if you configure an app to be launched with CTRL (say thunar, for the example) only, and another to be launched with CTRL+A (say the terminal), and you type CTRL+A, you launch thunar THEN terminal. (but they are spawned in the same key combination...)
The example I have given is pretty dumb, but some keys are in some systems used for many things, and it is useful. At least, I love it :)
The example I want to take is the windows'one. Keyboard shortcuts of the desktop environment are based on the SUPER key:
_ SUPER alone summon the equivalent of xfce4-popup-applicationsmenu
_ SUPER+E starts the file browser (you could use thunar here)
_ SUPER+L Lock the session
_ SUPER.....
It's pretty nice, because it allow to use all key combination not based on SUPER for other applications, giving something we could name a 'shortcut theme'* which give shortcuts easy to remember and avoid conflicts.
I don't know any app which use a windows shortcut... But I know that it's not possible (at least easy) for user in this closed desktop environment to modify windows shortcuts.
The fact is, when it is possible to modify and add some, conflicts can happen, because of the great variety of applications that we are able to add to our Linux distribution. If we take my first dumb example, CTRL+A is often used to select all items. If you assign CTRL to an application (by example, something to show a circle where your mouse is to enhance visibility of cursor) and want to select everything in an application, with CTRL+A, you make both things, and it could be not wanted.
To finish this long report, I would say that it could be relatively easy to implement: 'just' call the application when keys are released, not pressed.
The only problem I see now with this solution is to detect the FULL release of the shortcut. (else the problem will just be inverted, calling the application of the first key released in first and not the one of the first key pressed)
To conclude:
Thanks for this nice, customizable and light DE, and sorry for the long post.
*: now as I think of it, keyboard theme could be an interesting feature... but it's not the point here.
Version: git
Designs
Child items
0
No child items are currently assigned. Use child items to break down this issue into smaller parts.
I think we've had this discussion before and some of the cons i can remember was that it feels slow to wait for the release and it is also different from what's done normally (ie all gtk apps react on button press).
The <super>-only care is not completely true either, because if you use the bindings as described in the first post and quickly press <super>-e both thunar and the menu are shown. Maybe we can improve that, so the "long" bindings is executed and menu is omitted.
Sorry for the long laps of time, I didn't often look my mails those last times.
[quote]I guess that if we handle Super on release, it makes sense to handle Control,
Alt and Shift on release too. Do you both agree with that?[/quote]
I agree.
I think the easier way is to define "MOD" (modifiers, as opposite as "KEY" next on this message) keys, and make those keys react on release if no other key where pressed.
In this solution, you will have 2 different behaviors, depending on if there where another key pressed or not (please keep in mind that it's only a quick idea, I don't know how you have implemented things):
First case:
user press a MOD
user press another MOD (allow multiple MOD to be used)
user press a KEY
XFCE set a flag to disable calling the pure MOD binded app. (allow to cancel the call if user use a non-binded combination, by example in case the bind is used in another software. Avoid boring user can be interesting)
XFCE start the binded application if there is one
user press another KEY
software start the binded application if there is one
user release one of pressed MOD
user release last pressed MOD
XFCE look the flag: the flag is set, so do nothing
XFCE unset the MOD flag
end case
Second case:
user press a MOD
user press another MOD
user release a MOD
user release the last MOD
XFCE look the flag: the flag is not set, start the binded application
end case
Please keep in mind that I don't know internals of XFCE and I have wrote it in a few minutes, so I have probably miss some special cases.
I also have this problem, and I see that the bug report is 2.5 years old. If you aren't going to fix it, then please at least take the time to give us a pointer to the location in the code that handles shortcut processing so one of us can create a patch for it ourselves.
Created attachment 6422 [details]
Makes Super-key behavior windows-like
This patch addresses a behavior of Super-key like when you press in
combination with other keys, as well as for a single.
I would like to have this. Do I need to recompile everything? I'm on xubuntu
14.04 =x XFCE 4.12.0
You have to rebuild libxfce4kbd-private-2.so (or *-3, or maybe both).
@BIG,
Didn't worked here. Applied the patch, build and repack libxfce4ui on xubuntu 14.04 with XFCE 4.12.0 and didn't work. Well, at least <super> key is working on release now. But if I bind it alone to an app (open the aplication menu for example) I can't use it in a "combo" <super> + 1 to change to workspace 1 stops working, for example. If I don't use it alone, I can use it in "combos".
Created attachment 6422 [details]
Makes Super-key behavior windows-like
This patch addresses a behavior of Super-key like when you press in
combination with other keys, as well as for a single.
I would like to have this. Do I need to recompile everything? I'm on xubuntu
14.04 =x XFCE 4.12.0
You have to rebuild libxfce4kbd-private-2.so (or *-3, or maybe both).
@BIG,
Didn't worked here. Applied the patch, build and repack libxfce4ui on
xubuntu 14.04 with XFCE 4.12.0 and didn't work. Well, at least <super> key
is working on release now. But if I bind it alone to an app (open the
aplication menu for example) I can't use it in a "combo" <super> + 1 to
change to workspace 1 stops working, for example. If I don't use it alone, I
can use it in "combos".
libxfce4ui - is not the library you should rebuild.
You should rebuild libxfce4kbd-private-2.so or libxfce4kbd-private-3.so.
Created attachment 6422 [details]
Makes Super-key behavior windows-like
This patch addresses a behavior of Super-key like when you press in
combination with other keys, as well as for a single.
I would like to have this. Do I need to recompile everything? I'm on xubuntu
14.04 =x XFCE 4.12.0
You have to rebuild libxfce4kbd-private-2.so (or *-3, or maybe both).
@BIG,
Didn't worked here. Applied the patch, build and repack libxfce4ui on
xubuntu 14.04 with XFCE 4.12.0 and didn't work. Well, at least <super> key
is working on release now. But if I bind it alone to an app (open the
aplication menu for example) I can't use it in a "combo" <super> + 1 to
change to workspace 1 stops working, for example. If I don't use it alone, I
can use it in "combos".
libxfce4ui - is not the library you should rebuild.
You should rebuild libxfce4kbd-private-2.so or libxfce4kbd-private-3.so.
I know.
New tests, it seems like the shortcut set for on Keyboard Settings is conflicting with the ones on Window Manager Settings.
If I use <super> key alone to open an app. And <super> + <an other key> to open an app, it works. But it doesn't work for window manager with <super> is set alone to an app.
If I set <super> alone to a WM action, nothing happens.
If I use <super> key alone to open an app. And <super> + <an other key> to
open an app, it works.
Yep. This is exactly intended behaviour.
But it doesn't work for window manager with <super> is set alone to an app.
If I set <super> alone to a WM action, nothing happens.
Well, it really seems that my patch somehow conflicts with WM-settings. I
will take a look at it. Thank you for the report!
@BIG,
Could you replicate it?
Thank you for the patch. This is exactly what I was looking for.
Well, I'm too lazy to go back to the mainstream again >.<
I will be waiting for the fix =).
By the way i have reverted my path and try user shortcust Super+Key in WM. I.e. Super+D for Show/Hide desktop, Super+1/2 to switch between Workspaces. And it does not work. But when i remove Super_L (standalone) from keyboard shortcuts it's works normal. Then i applied my patch again and test: still works fine.
So i see this problem does not caused by my patch but it is bug in XFCE.! :)
By the way i have reverted my path and try user shortcust Super+Key in WM.
I.e. Super+D for Show/Hide desktop, Super+1/2 to switch between Workspaces.
And it does not work. But when i remove Super_L (standalone) from keyboard
shortcuts it's works normal. Then i applied my patch again and test: still
works fine.
So i see this problem does not caused by my patch but it is bug in XFCE.! :)
Hmmn. I will revert then and wait for XFCE's developers to fix this in the future.
BTW, if the whole idea behind this change is to use a single modifier as a
shortcut, that seems wrong in the first place.
I always felt XFCE behaves weird about keyboard shortcuts. A lot of distros binds <super> key to whisker menu, for example, and this drives to strange behavior (the menu opening when you use <super> as a modifier to other command).
What I feel it's as if the keyboard shortcut for apps conflicts with WM shortcuts, or they both understand <modifiers> keys differently. The <alt> modifier, for example, alone its standard for showing the menu in some apps and works well as a modifier, but, if you assign <alt> alone to open an app, <alt> as a modifier is dead. You can't use <alt> + <space> anymore, for example.
It's like to different things controls the keyboard and they are not talking.
BTW, if the whole idea behind this change is to use a single modifier as a
shortcut, that seems wrong in the first place.
I always felt XFCE behaves weird about keyboard shortcuts. A lot of distros
binds <super> key to whisker menu, for example, and this drives to strange
behavior (the menu opening when you use <super> as a modifier to other
command).
Which is to be expected, becauset he Wisker menu will have a passible grab on the modifier, triggering any time the modifier is pressed.
Which is exactly why I reckon using a single modifier as a shortcut is wrong, modifiers are, as their name implies, to modify the behavior of other keys.
What I feel it's as if the keyboard shortcut for apps conflicts with WM
shortcuts, or they both understand <modifiers> keys differently. The <alt>
modifier, for example, alone its standard for showing the menu in some apps
and works well as a modifier, but, if you assign <alt> alone to open an app,
<alt> as a modifier is dead. You can't use <alt> + <space> anymore, for
example.
Same thing, don't use Alt (a modifier) alone to open another app.
It's like to different things controls the keyboard and they are not talking.
Every single application is free to have a passive grab on any key and react the way it wants.
BTW, if the whole idea behind this change is to use a single modifier as a
shortcut, that seems wrong in the first place.
I always felt XFCE behaves weird about keyboard shortcuts. A lot of distros
binds <super> key to whisker menu, for example, and this drives to strange
behavior (the menu opening when you use <super> as a modifier to other
command).
Which is to be expected, becauset he Wisker menu will have a passible grab
on the modifier, triggering any time the modifier is pressed.
Shouldn't this be on release, not on press?
Which is exactly why I reckon using a single modifier as a shortcut is
wrong, modifiers are, as their name implies, to modify the behavior of other
keys.
What I feel it's as if the keyboard shortcut for apps conflicts with WM
shortcuts, or they both understand <modifiers> keys differently. The <alt>
modifier, for example, alone its standard for showing the menu in some apps
and works well as a modifier, but, if you assign <alt> alone to open an app,
<alt> as a modifier is dead. You can't use <alt> + <space> anymore, for
example.
Same thing, don't use Alt (a modifier) alone to open another app.
It's like to different things controls the keyboard and they are not talking.
Every single application is free to have a passive grab on any key and react
the way it wants.
that would break existing established workflows such as alt-tab for example.
I've just checked Alt+Tab with my patch - everything works fine, so no problem here.
(In reply to Olivier Fourdan from comment 30)
BTW, if the whole idea behind this change is to use a single modifier as a
shortcut, that seems wrong in the first place.
A millions of people (include me) every day use Windows shortcuts - Super_L(standalone) to launch/hide Start Menu, Super_L+Key to launch actions. And they finds this scheme very usefull.
Of course, it's possible to make a checkbox in the settings for enable/disable this behavior.
If support for such features opens up some other bugs - it is all fixable anyway.
I know, this shortcuts looks like a minor problem, but a hundreds of such "small issues" are prevent millions of people switch from Windows to Linux fulltime.
Which is to be expected, because the Whisker menu will have a passible grab
on the modifier, triggering any time the modifier is pressed.
Shouldn't this be on release, not on press?
That wouldn't make much difference, you'd get the menu open on the key release (instead of key press) while defining another shortcuts using the same modifier.
There is no centralized shortcut management in X11, every app is free to grab keys (including modifiers) and do whatever they want with them, so there is no real "fix" for this, triggering actions on key press or key release doesn't change that problem.
Which is to be expected, because the Whisker menu will have a passible grab
on the modifier, triggering any time the modifier is pressed.
Shouldn't this be on release, not on press?
That wouldn't make much difference, you'd get the menu open on the key
release (instead of key press) while defining another shortcuts using the
same modifier.
There is no centralized shortcut management in X11, every app is free to
grab keys (including modifiers) and do whatever they want with them, so
there is no real "fix" for this, triggering actions on key press or key
release doesn't change that problem.
Well... ok then.
I'm not a developer, I don't know how this works behind the scene. I'm just a desktop user who likes XFCE because I can use it the way I like, at least most things as I like.
I like the way gnome-shell behaves about keyboard shortcut, but I don't like gnome-shell. If we can't have that way of handle keyboard in XFCE, no problem. I will forget about it. I just whish things were more keyboard driven, as gnome-shell.
Yeah... xcape is well known crutch for this problem.
As for me i didn't like such dirty hacks so i prefered to develop a patch for XFCE. Maybe i will create project on GitHub to host my patches.
Which is to be expected, because the Whisker menu will have a passible grab
on the modifier, triggering any time the modifier is pressed.
Shouldn't this be on release, not on press?
That wouldn't make much difference, you'd get the menu open on the key
release (instead of key press) while defining another shortcuts using the
same modifier.
So the desired behavior is achieved by breaking down key combinations into presses and releases. Super+E is actually Super press + E press. Super (standalone) is actually Super press + Super release, where any keys in between break the combination.
So the desired behavior is achieved by breaking down key combinations into
presses and releases. Super+E is actually Super press + E press. Super
(standalone) is actually Super press + Super release, where any keys in
between break the combination.
Yes. However, if you want to emulate 100% of the capabilities of Windows, there's a few other cases that may not be handled with simply tracking the press/release of each key. For example, The following sequence in Windows:
Super press -> E press -> E release -> R press -> R release -> Super release
will invoke the shortcuts for both Super+E and Super+R, even though Super was not released and repressed between pressing E and R. I'm no coder and don't know how the underlying keyboard system works, but perhaps something like this:
when.keypress ($key) {
if (
SUPERisdepressed=1)thendoSUPERand[
key]function
if (
CTRLisdepressed=1)thendoCTRLand[
key]function
if (
ALTisdepressed=1)thendoALTand[
key]function
else passkeytoprogram($key)
}
But that's probably horrible and inefficient with whatever keyboard interfaces are present. The basic idea is that instead of triggering on a specific pattern of presses and releases that includes the modifier keys, keep track of which modifiers are pressed at any given time, so that it doesn't matter which order you press the modifiers in, or whether the modifier is held down during multiple keycombos.
Hello there. Maybe someone can make patch to change other mod-keys (Ctrl, Alt, Shift) to work on release?
I'm working on Kali Linux xfce 2016.2 and this issue with shortcuts gives me headache...
I also think that this is a missing feature and I would love to see it in Xfce.
(In reply to Olivier Fourdan from comment 32)
Which is exactly why I reckon using a single modifier as a shortcut is
wrong, modifiers are, as their name implies, to modify the behavior of other
keys.
I don't think that it matters whether using only a modifier key as a shortcut seems wrong on a superficial level or not. While not allowing this might look like a senseful design decision on a purely theoretical level, there are clearly many people who would like to use this feature and have used it productively outside of Xfce for a long time. I would argue that, at the end of the day, the DE is there to provide users with a good working environment and that this is is more important.
(In reply to Olivier Fourdan from comment 35)
That wouldn't make much difference, you'd get the menu open on the key
release (instead of key press) while defining another shortcuts using the
same modifier.
There is no centralized shortcut management in X11, every app is free to
grab keys (including modifiers) and do whatever they want with them, so
there is no real "fix" for this, triggering actions on key press or key
release doesn't change that problem.
As far as I can see this doesn't really matter, because the desktop environment is responsible for keyboard shortcuts. There should not be a problem in exercising some control over which key presses are registered as shortcuts and which aren't. The portion of Xfce that is responsible for keyboard shortcuts then becomes this "centralized shortcut management".
Some approaches have already been stated. Here is what I thought of:
Shortcuts for single modifier keys (e.g. only Super, or only Alt) are executed on key release.
Shortcuts for single or multiple modifier keys in combination with a single normal key (e.g. Super+A, or Alt+F1) are executed on key press for the normal key. You could query for the normal key first, and only then look if the necessary modifier key is held during the press).
Shortcuts for single or multiple modifier keys in combination with multiple normal keys (e.g. Super+Left+Up) are executed on key press for "the last" normal key that is pressed. This essentially follows the same rules as the previous situation; you look for one of the normal keys and then consecutively check if all necessary other keys (including the modifier key) are held during the press.
The last point might sound strange at first, but it would enable more intuitive controls for window tiling. For example, you could use Super+Up+Right to tile a window to the upper right corner.
if Super is pressed and no other key is pressed afterward in 0.2s bring menu,
otherwise treat it as someone will press another key with Super
Also to note that this bug was assigned
2015-03-10 12:01:22 CET
and it's importance is Low minor
I think it should be reassigned as a current asignee haven't solved it in a year and change importance - to have a Windows like shortcut behavior (which is same as Gnome 3 as far as I remember) is not something should have Low minor importance but rather as "Medium".
This, a million times this, I was actually loosing my mind today, as a new Linux user, recently moved from Windows, I want my migration to be gradual and find these kinds of shortcomings a bit tedious.
Can its priority not be changed at all ? It definitely is something wrong with how shortcuts are handled, there is also a patch.
Please guys, fix this, it is 7 years old already.
Personnally, I tend to believe that nothing should happen on keydown of modifiers. A flag should be set when a plain key is used in addition, so that we know on release whether the modifier has been consumed, or deserves a consideration of its own ; we don't need to handle repeat on those anyway, so I don't see the point of doing otherwise
Now, and this is the real point of my post, not everyone seems to realize how paramount this bug is.
I know at least one entire R&D (batmaid.com) who have opted for Windows because of that very bug (and the non-usability of Gnome and lack of stability of KDE) : basically, standard window-tiling does not work with XFCE because of that, period ; or, that's the way they perceived it; they did not even go down to this hard-to-find bug report.
They are now a ten-guys team and growing. and I am sure hundreds have left at least XFCE just because of that silly sandstone. We could just as well break Ctrl+F4, Ctrl+C and Ctrl+V, just to marginalize Linux a bit further ; I am sure Microsoft would love it.
So, please stop discussing and fix it either way, plus include default customization for tiling : Super+Left, etc There are hundreds of users at stake, no kidding.
Thanks BIG, I'm attaching to this bug your patch with my small improvements.
It works very well, unfortunately xfwm4 bindings to Super+<Any Key> don't work anymore. My X11 knowledge is rather limited, but I think this is because xfsettingsd (via libxfce4ui) grabs the Super key thus any event concerning it is not passed to xfwm4.
<rant mode>
This "odd" behavior is one of the top complaints I receive from users new to Xfce and I myself am still very annoyed by it after all these years, devising key combinations with ctrl|shift|alt that don't conflict with apps is a PITA. The bottom line is: Super is not an ordinary modifier, anyone who has ever used another desktop environment (Gnome, KDE, Cinnamon, Windows...) expects Super alone to invoke an app launcher and a combination of it plus other keys to (usually) manage windows (show desktop, tiling, etc).
</rant mode>
@olivier, I agree that handling keys on release would not help, in fact some use cases (e.g. alt+tab) would be affected. Is there any reason why xfwm4 has its own keys grabbing/handling? Historical or to not depend upon xfsettingsd? Since you're the X11 expert around and xfwm4's maintainer, do you happen to think of any way to get around the key grab limitation?
Patch 7635, "Special super key handling": super.patch
Please, this is bugzilla, not your favorite social network, rants do not belong to bugzilla.
This "odd" behavior is one of the top complaints I receive from users new to
Xfce and I myself am still very annoyed by it after all these years,
devising key combinations with ctrl|shift|alt that don't conflict with apps
is a PITA. The bottom line is: Super is not an ordinary modifier, anyone who
has ever used another desktop environment (Gnome, KDE, Cinnamon, Windows...)
expects Super alone to invoke an app launcher and a combination of it plus
other keys to (usually) manage windows (show desktop, tiling, etc).
</rant mode>
The Super key has its own special treatment in mutter [1] (the “overlay” key), it's not a regular all-purpose key, not even in GNOME... There is no point in assigning Super for any special purpose in xfce.
@olivier, I agree that handling keys on release would not help, in fact some
use cases (e.g. alt+tab) would be affected. Is there any reason why xfwm4
has its own keys grabbing/handling? Historical or to not depend upon
xfsettingsd? Since you're the X11 expert around and xfwm4's maintainer, do
you happen to think of any way to get around the key grab limitation?
Keyboard events are routed to the window with keyboard input focus, meaning that the window manager must acquire a grab on its own if it ever wants to receive the keyboard events for its own use (i.e. its own keyboard shortcuts).
What we have here is dilemma: the technical side that claims super key is a only modifier key, but open to please users if it can be done cleanly, without hacks. On the other hand, many users coming from Windows (including myself) frown upon this limitation and refuse get used to new shortcuts. The ksuperkey author summarizes why he created it and provides some reasons why the problem exists in first place: https://blog.hanschen.org/2012/10/17/open-application-launcher-with-super-key/ It's interesting to learn that KDE3 had a special handling for super key but was removed "because it was a hack and quite broken".
In the next days, I hope to survey other DEs to check if they have any special handling for super key and how they accomplish it. But don't hold your breath waiting for me, anyone is free to propose different solutions (BIG's patch works well, but once xfsettings grabs super key, xfwm4 will not receive any events for bindings that use it as modifier). Meanwhile users should consider ksuperkey (or xcape itself).
Gnome: Similar behavior and code to cinnamon (obviously)
Plasma:
Super alone (handled on release) opens menu
Super+arrows tiles windows (not the default, can be set)
Super+p opens display switcher
No traces of XIGrabKeycode, XGrabKey or XRecord in kwin
I couldn't find out what's their "settings-daemon" or the component responsible for global hotkeys
Mate: Super alone cannot be assigned to anything
i3: Super ($mod) alone cannot be assigned to anything
Unless XInput2's grab of Super does not prevent other windows to receive events of Super as modifier, I couldn't find the proper fix :'(
XRecord is too much hack to be introduced in Xfce's code IMHO.
For now, xcape -e 'Super_L=Control_L|Escape' on start up frees Super to be used as modifier, not an official fix, but a simple workaround.
Perhaps Xfce would not need to wait that user released the keybinding, but it could use software way to release the keybinding so that it does not interfere the command to be executed. That could be optional, if there is some harm of it.
And this eager shortcut behavior causes not just harmless inconvenience but also systematic problems beyond xfce components. For example, assigning ctrl+shift (e.g. to keyboard switching) disables all the common shorcuts involving ctrl+shirt (e.g. restore closed window in Firefox/Chrome). When setting a shorcut, the user should be really only responsible for that particular combination of keystrokes instead of the whole exponential-sized set of enclosing combinations.
Fwiw, the problem with ctrl+shift+something shortcuts not working when ctrl+shift is used for keyboard layout switching is a bug of xorg, not xfce, see
https://gitlab.freedesktop.org/xorg/xserver/issues/258 (migrated version)
https://bugs.freedesktop.org/show_bug.cgi?id=865 (better readable)
xorg handles keyboard layout switching, not xfce (xfce just sets the shortcuts of the xkb extension). The xkb extension standard would have to be extended and the x server extension changed accordingly for a fix. No one has done in the 15 years that bug stands.
Anyhow I understand the original bug here - isolated press and release of super key (winkey) is a well defined act that does not hinder the use of super as a modifier (pressing additional key with super already pressed cancels the act of isolated press and release of super).
btw: ksuperkey is fork of xcape to use in KDE (basically, the change is only the default hotkey) and xcape is as workaroung mentioned many time above ;-)
Is anything going to be done about this 'on key release' handling issue?
I believe actually in Xubuntu 16.04 it worked okay. Now that I upgraded to 20.04 it doesn't work again.
It would be really good to have this functionality on par with other desktops. Again, the easiest comparison candidates are MS Windows and Cinnamon. I suspect there may be a lot more affected users who would like to see this fixed but they either didn't take the time to look for this Issues page or just can't be bothered to voice their concerns.
Devs, please try to allocate some time and resources to look into this. Thank you for delivering an amazing desktop and keeping it great.
Another user looking for this to be modified to behave like other desktops.
I use xfce to try and speed up everything so I can work faster, and not having super working as a modifier is annoying and slow-down things a little bit.
Is anyone even reading the comments from bugzilla? I don't think so...
All in all, there is no easy fix, until someone comes up with a proper solution (merge requests are welcome!), you can use Super key alone and as modifier with a very easy tweak:
install xcape
add to session autostart: xcape -e 'Super_L=Control_L|Escape'
assign Ctrl+Esc as shortcut to appfinder or whatever you to launch apps
Hi, I'm taking a look at this issue right now and it seems that this topic has grown stale, but it is particularly important with Wayland coming in the future. I don't really know what else to do other than "bump" this issue since no discussion has taken place for 2 years and no actual work in 4 on this problem.
From what I can tell, shortcuts are simply parsed from the state of the keyboard (which keys are currently pressed down). Instead, perhaps if an action is set to occur on the Control_L key, for example, set a flag and, if another key is pressed before Control_L is released, unset that flag. If that flag is still set, then the command should be run when control is released. That might not be able to be implemented in the grabber file, though. Perhaps someone with actual experience unlike myself could consider this issue?
I tried installing libxfce4ui-4.18.6 on my clean & fresh XUbuntu-24.04. I want to change keyboard layout on Ctrl+Shift, but when I use ANY hotkey combination including Ctrl+Shift, the sequence is interrupted and the language is changed.
No, this issue is fixed best we can: when a shortcut is a modifier alone, it's activated on release, otherwise it's activated on press. This makes it possible, for example, to use the Super key to display the clipman menu, while having a Super+T shortcut to open a terminal, without the clipman menu being displayed when a terminal is opened. If we activated all the shortcuts on release, we'd just have the same problem as before on release instead of on press.
Furthermore, the layout change shortcut is not managed in libxfce4ui but in xfce4-settings, and I'm afraid there's not much we can do to change the way key events are consumed, as it's an XkbOptions, so managed internally by X11 if I'm not mistaken.
In any case, I can confirm that when the Super key is used as above for the clipman menu (i.e. activated on release), the shortcut no longer works if the Super key is also used to change layout. So I don't think activating on release or press changes anything here.
All that said, feel free to open a new issue at xfce4-settings if you like :)