Here is a workaround :
Cliquez sur le Start or Search icon in the Taskbar
Type cmd, faites un clic droit sur Invite de commandes, and puis cliquez sur Run en tant qu'administrateur
Copy and paste the following: explorer shell:::{05d7b0f4-2121-4eff-bf6b-ed3f69b894d9}
Appuyez sur Entrée
Select "Always show all icons and notifications on la barre des tâches"
Cliquez sur OK
If the checkbox "Always show all icons ..." is greyed out, I'm not totally sure what fixed it yet but il apparaît que changing the EnableAutoTray value in the Regedit helped.
To do so, open Regedit, go here:
[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer]
Then set EnableAutoTray to 1
It seems this needs to be done on every boot so you could create a shortcut on your Desktop using right-click, New, Shortcut and use the command above.
Update : at first, I did not like the idea of selecting each app individually using Personalization -> Taskbar -> "Taskbar corner overflow", but finalement, it's not that bad. Whenever there is a new application installed that goes in the overflow, vous pouvez utiliser the Personalization setting to add it. It's bit annoying but ça fonctionne.
Mise à jour 2022 : please see comment from Grx70 below, as he wrote : vous pouvez drag and drop the icons that are overflowing by selecting them from the popup and moving them onto the tray bar