Hi, you don't say how you pinned the icon to the Taskbar - since there are several ways.

Try unpinning from the Taskbar, then start Firefox from its program on the Start Menu, now right click its running Taskbar icon and pin to Taskbar.

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Did you check the properties of this icon to see what is wrong (path to icon or path to Fx application)?

This is exactly what I did. I startet Firefox, rigtht klick icon on Taskbar and pinned it to Taskbar. First all is OK, but after the next uptate of Firefox, his icon lost its color, it was only a white regtangle. Klicking it produces a propt saying that the target does not exist and ask to delete the icon. When I press no and right klick this icon, I can see a proper Firefox icon in the list. Firefox starts normally, if I klick it. To repair the ikon, I do several times unpin and pin it. Then it works. But this could not be the normal way.

Did you check the properties of this icon to see what is wrong (path to icon or path to Fx application)?

No. I can do it, when the problem appears again after the next update.

reiner.kissel said

Firefox asks me to apply the newest update. I accept. When I want to restart firefox with the icon I have fixed at the task bar, windows tells me that the icon is invalid. After fixing a new icon to the task bar, all is OK. But that means several klicks extra after every update. Some month/years ago, this was not necessary.

After the last update all was ok.