Problem with some keyboard shortcuts

[CinemaScope]

What is your operating system?
Linux Mint 21.1 (with Mate).

What is your Shotcut version (see Help > About Shotcut)?
23.06.14 (AppImage).

Can you repeat the problem? If so, what are the steps?
(Please be specific and use the names as seen in Shotcut, preferably English. Include a screenshot or screen recording if you can. Also, you can attach logs from either View > Application Log or right-click a job and choose View Log.)

Don’t know if this is just happening on my computer, but I have experienced some keyboard shortcut issues.

I can zoom the timeline in and out when using the timeline zoom icons, and I can zoom out using the keyboard shortcut (- key), but when I try to zoom in (+ key), nothing happens.

I can drag slider controls on filters, but when I highlight the control values to make fine changes with the keyboard (up and down arrow keys), nothing happens.

[MusicalBox]

@CinemaScope

I can zoom the timeline in and out when using the timeline zoom icons, and I can zoom out using the keyboard shortcut (- key), but when I try to zoom in (+ key), nothing happens.

Plus and minus keys works properly for me (on Windows) to zoom the timeline in and out.
Maybe you accidentally deleted the + key shortcut in Help > Actions and Shortcuts ?

@CinemaScope

I can drag slider controls on filters, but when I highlight the control values to make fine changes with the keyboard (up and down arrow keys), nothing happens.

Try the mouse wheel when hovering a slider or parameter value

[shotcut]

@CinemaScope

when I try to zoom in (+ key), nothing happens

This works for me on GNOME in Ubuntu 22.04 (as well as Windows and macOS). There is some conflict on your setup that we cannot fix. You can define an alternate shortcut in the Actions and Shortcuts dialog shown above.

the control values to make fine changes with the keyboard (up and down arrow keys), nothing happens

This is fixed for the next version.