I have the exact same issue "I just updated to the latest version of Firefox (auto), suddenly now, when I right click and quit upon closing, another icon appears, quitting again, another appears. I remove from doc, but same thing happens again upon quitting. Any help with this greatly appreciated. "

I think I've found a solution. System preference > dock > uncheck show recent applications in dock. Worked for me.

Hello all those who have been trying to help me with this problem. I have just done as bablouie above suggests and that has stopped the appearance of strange new Firefox aliases in the toolbar qwhen I shut down Firefox. It is a solution but I guess the question remains: why was this penomena happening when before, when "show recent application" was unchecked, these strange artifacts were not appearing. Still I guess a bug that should be worked out.

See also:

• /questions/1410745 icons appear in desktop toolbar evertime I open Firefor

It worked good for now. bablouie is right. I think that the version 112.0 (64-bit) is very bad. I will have to wait for the next version.

I noticed that this version caused my Firefox browser to slow down for showing up any website. My Safari browser was a normal speed. The previous Firefox version was fine.