okular warns about missing breeze icon theme

[cdepillabout]

Issue description

When starting okular, it gives warnings that an icon theme is not installed:

$ okular /path/to/my.pdf
Icon theme "breeze" not found.
Icon theme "breeze" not found.
Error: standard icon theme "breeze" not found!
Icon theme "breeze" not found.
Icon theme "breeze" not found.
Error: standard icon theme "breeze" not found!

What's going on here? Do I have to manually install the breeze icon theme? Would this be the breeze-icons package?

As an end-user, it would be nice if the okular derivation just pulled in an icon theme that would be used if I don't already have one installed. If it is known that okular gives warnings without an icon theme, it would be nice if it just worked correctly when installed.

Steps to reproduce

I've installed okular with nix-env in 18.09.

In my /etc/nixos/configuration.nix, I've enabled the X server, but I don't have any desktop environment enabled:

{
   services.xserver.enable = true;
}

Technical details

• system: "x86_64-linux"
• host os: Linux 4.14.90, NixOS, 18.09.1822.0a8f35c998f (Jellyfish)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.1.3
• channels(root): "nixos-18.09.1822.0a8f35c998f"
• channels(illabout): "unstable-19.03pre164715.201d739b0ff"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

[cdepillabout]

Pinging @ttuegel and @vandenoever, since it looks like they are maintainers for the KDE applications.

[ttuegel]

Leaving this note to myself: An appropriate solution would be to wrap KDE applications for XDG_DATA_DIRS.

[FRidh]

Fixed in #54525

[newptcai]

I have the same problem with version 21.12.3

[ghost]

@newptcai Same here. apt install breeze-icon-theme has fixed that for me.

[me-at-gitt]

Same here. apt install breeze-icon-theme has fixed that for me for okular 21.12.3. But this is just a fix, not a solution.

[JohnAZoidberg]

Same here. apt install breeze-icon-theme has fixed that for me for okular 21.12.3. But this is just a fix, not a solution.

What? Are you using nix on Debian/Ubuntu? If you're not using nix, then this is the wrong repo to comment on.
I don't see this warning on GNOME/Wayland on NixOS 24.05 with Okular 23.08.05.