As a Windows user, I'm not familiar with this symbol. Could you possibly post a screen shot of it, or if there are images of it in an image search, link to an image of it.

This support article has suggestions on taking screen shots: How do I create a screenshot of my problem? Please cut out or blur any sensitive information before attaching the image to your reply.

Oh, a new update is available. Could the symbol indicate that? You usually can update using the "About Firefox" dialog on the Help menu. (I say usually because after a new version is released, the update notification typically is trickled out over a couple days.)

the symbol is a circle with a line through the middle of it.......I'm sure there's a more exact name than the "no" sign. I'm sure you've seen it before on other things.....it's on posters and signs everywhere. I'll try to download the must current version.......thanks

I have not heard of such.

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