I'm running Zotero 7.0.8 (64 bit) in Firefox 131.0.3 (64 bit). I have pinned Zotero to the taskbar. When opening Zotero it puts a duplicate icon in the taskbar. The duplictae has a bar beneath indicating that the program is open. The original icon does not but when right clicking on it it presents Zotero (4) and Unpin from taskbar. Selectin Zotero (4) does not appear to do anything. Selecting Unpin from taskbar, does what it says and leaves the application open with the other icon remaining. When Zotero is now closed, there is no icon in the taskbar.
The bug that needs fixing is that when the taskbar pin is selected and Zotero opens, placing an underscore under the icon as it correctly does, there should be no second icon appearing in the taskbar.