Maybe related, Nemo Shift+Click or Ctrl+Click doesn't work either.

linux mint 21.3
cinnamon 6.0.4
nemo 6.0.2
kernel 5.15.0-91-generic

I have the same problem, Shift and Ctrl only work when writing text, if im in a game or in nemo they dont do anything.
My Alt key also doesnt work

Seems like key-down events aren't sent for shift/ctrl/alt. Key-up events for them are however.

Fedora 39 with cinnamon 6.0.4, same problem - affects all applications as far as I can tell

If you press Ctrl having different window focused, and then click within the desired window, it works.

Fedora 39 with Cinnamon 6.0.4

linux mint 21.3 cinnamon 6.0.4 nemo 6.0.2 kernel 5.15.0-91-generic

I have the same problem, Shift and Ctrl only work when writing text, if im in a game or in nemo they dont do anything. My Alt key also doesnt work

Also have the same issue when running applications such as games. Pressing Shift key does nothing.

Linux mint 21.3
Cinnamon 6.0.4
Kernel 6.5.0-28-generic

i just tried cinnamon 6.4.0 on arch linux and this still doesnt work
is it going to be fixed by 22.1?

i just tried cinnamon 6.4.0 on arch linux and this still doesnt work is it going to be fixed by 22.1?

so far, that doesn't seem to be the case; this bug is still present in the 22.1 beta...

So interestingly, if you do CTRL+Shift+Click it works so this may be some simple keymap issue?

thats interesting
i tried it out and found out that the order of the keys matters

ctrl+shift+click = ctrl+click
shift+ctrl+click = shift+click

the second key can also be alt

Surely this is something that can be programmed around...

yeah, i would try to do it myself but i don't know if this is inside cinnamon or muffin
it would take days to go through all the code

I am having the same issue, on Linux Mint 22.0, but I'm confident that I have identified the cause and here are my steps of logic:

• This seemingly happens only with Wine/Proton. I haven't found a native application that has this issue, but I could be wrong. (EDIT: see below)
• Running xev shows that no KeyPress or KeyRelease events are received for the Ctrl, Shift or Alt keys. This would suggest that pressing those keys would not work on their own, as in without another key. As a test, I started Kerbal Space Program (a native Linux game) which I know utilizes the Shift key, and pressing it did not work. This output from xev running in Xorg:

KeyPress event, serial 38, synthetic NO, window 0x3c00001,
    root 0x5f6, subw 0x0, time 150024652, (110,84), root:(160,628),
    state 0x0, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyRelease event, serial 38, synthetic NO, window 0x3c00001,
    root 0x5f6, subw 0x0, time 150024788, (110,84), root:(160,628),
    state 0x1, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

• Running a Wine application with WINEDEBUG=msg (debug window messages) shows differing results depending on the driver: with the X11 driver it gets no events for the Ctrl, Shift key. With the Wayland driver, only WM_KEYUP messages are sent.
• Running ANY Wayland application (native or otherwise) with WAYLAND_DEBUG=1 shows that the compositor is only sending key up messages, no key down messages.

Consider this output from Weston, when I press the Shift key:

[2660826.628] [email protected](1130, 141435685, 42, 1)
[2660827.030] [email protected](1130, 1, 0, 0, 0)
[2660922.626] [email protected](1131, 141435781, 42, 0)
[2660922.961] [email protected](1131, 0, 0, 0, 0)

And this output with Muffin (Cinnamon):

[2446976.281] [email protected](3049, 1, 0, 0, 0)
[2446976.388] [email protected](3050, 141221834, 42, 0)
[2446976.436] [email protected](3051, 0, 0, 0, 0)

The last parameter of this event is the keystate, 1 being pressed (key down) and 0 being released (key up). (Source) As you can see, there is a key down event missing. This does not happen with normal keys, only the modifier keys. Xwayland, GTK and Qt applications don't seem to mind this, but it seems Wine does. I suspect this is due to how Wine's input model differs from X11 and Wayland.

EDIT: more info

EDIT 2: I have found the cause of this bug and I've made a pull request to fix it.

works fine just like on x11 with the fix
i tested it on mint 22.0 in a vm

Just tested this with the fix on mint 22.0 with wayland experimental. Seemed to do the trick. Blender shift/ctrl key works as expected. Steam games (Enshrouded) also works perfectly.