The Windows notification area overflow area was implemented by Microsoft to allow users to organize notification icons and cut down on visual noise when working on the desktop. There was never, and has never, been any documented API to allow developers to FORCE a notification icon to show in the main system tray.
This decision to not allow devs/software to override explicit user preference was by design.
But apparently that didn't sit well with the developers over at Dropbox. For years now, Dropbox has forcibly overridden the user preference to put the Dropbox notification icon into the overflow menu. And it's done by altering this registry key:
This is a binary key that requires more than just a simply edit to force a notification icon to be shown, it actually needs some rudimentary decoding/encoding to change the value for a single notification icon. And that's because this key isn't meant to be touched by anything other than the operating system. Dropbox forcing itself to be always visible in the notification area isn't some minor error or glitch, the only way it can occur is by precisely and very consciously coding for that behavior to occur. Process Explorer confirms this: Dropbox very actively and deliberately tampers with this key on every install, every update and (now more recently), every startup of the application.
My question to the Dropbox developers is this: If my Anti-Virus, Crypto-Wallets and Password Managers all manage to keep themselves hidden in the notification overflow, what makes you think Dropbox has the right to override user preference? What exactly was the reasoning behind this decision, and will it continue? Why exactly does the Dropbox development team think it has the right to use undocumented methods that no other legitimate software company uses?
This behavior is looking very much like the tactics malware uses to co-opt operating system settings, and the excuse that this notification icon is forcibly shown just in case the "user doesn't know where to find it" may have worked in 2001 but it definately doesn't cut it in 2021.
"There is no way for applications to programmatically always show themselves top level on the system tray either on first install or at any time during runtime. This is one of several changes we’ve made in Windows 7 in an effort to produce a cleaner, quieter desktop that is in the user’s control to customize the top level with their favorite applications and icons.
We keep the user in control of the notification area by not allowing programmatic promotion (other than temporarily or to show a notification). Assuming the machine is sufficiently quiet, when you first add your icon with Shell_NotifyIcon(NIM_ADD, ...) it will be shown on the taskbar for 45 seconds, then move into the overflow
thereafter. If the user promotes an icon, it will always live on the taskbar. If the user demotes it, the icon will never be seen on the taskbar. Any promotion needs to be user initiated. We’ve made this much easier in Windows 7 via drag/drop & through the Notification Area Icons control panel, and what we’ve seen in usability studies and based on beta feedback, is that users have no difficulties discovering how to customize notification behavior and will promote the icons they want quick access to."