window icons not working

[florianfelix]

Describe the bug
Window Icons are not displayed

To Reproduce
I have setup a fresh project at https://github.com/florianfelix/downloader
Neither in dev mode nor final build are the window icons displayed correct.
The dev window has some other icon and the final build has some kind of placeholder image.
Pictures and tauri info are in the readme of the project.

Screenshots

Platform and Versions:
Operating System - Manjaro, version 21.0.5 X64

Node.js environment

Node.js - 16.1.0
@tauri-apps/cli - 1.0.0-beta.1
@tauri-apps/api - 1.0.0-beta.1
Global packages

npm - 7.12.1
yarn - 1.22.10
Rust environment

rustc - 1.52.1
cargo - 1.52.0
App directory structure

/dist
/src-tauri
/src
/.git
/node_modules
/public
App tauri.rs - 1.0.0-beta.1

build-type - bundle

CSP - default-src blob: data: filesystem: ws: http: https: 'unsafe-eval' 'unsafe-inline' 'self' img-src: 'self'

distDir - ../dist

devPath - http://localhost:3000/

framework - Vue.js

Additional context
OS is Manjaro XFCE