Toolbar Icon missing Debian 12, GNOME
Some other versions of Debian desktops, other Linuxes are okay.
A solution given by Dropbox is to download a newer version of Dropbox than is in the Debian Repositories, which is dated this year, and install that. This did not resolve the issue.
At the present time, I do not have Dropbox installed on this PC because I do not have the space. If I had the icon, I could selectively turn off local synchronisation of some directories and resolve the space issue.
I observe that there is much discussion on this issue, but not specifically for Debian GNOME.