This is a bug in Waybar, which I suppose you are using. When app create tray icon before Waybar finish launching it is not shown.
Create a script like autostart.sh, start waybar there, then do like 5 second delay and start apps that has tray icons.
or just slap a "sleep 5 &&" in front of the command in your hyprland config. e.g. "exec-once= sleep 5 && qbittorrent"
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Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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