[Evolution] Application icons duplicate in panel/taskbar upon opening the application

[Simon Long <evolution-list b278 emailuser net>]

Hi there,

I'd be grateful for any tips on resolving the following minor issue, please:

Issue:  Application icons duplicate in panel/taskbar upon opening the application.  

Version: Evolution 3.40.1  via Flathub on Linux Mint 20.1 (Desktop: Cinnamon 4.8.6)

Expected behaviour: On left click, application icon (white open envelope with small purple clock) pinned to panel becomes active (underlined in Mint), application opens.  Thereafter, same icon can be used to toggle application window between minimize/active window states. 

Actual behaviour:  On left click, application icon pinned to panel remains in inactive state (not underlined), additional icon appears (red and white clock design) on the right of the panel row of application icons, and behaves as the active application icon; thus two different icons (one inactive, one active) are present. 

I have uninstalled and reinstalled to no avail, and I do not have this behaviour with other applications. 

Many thanks!

Simon