How do I turn off pop-up prompts from Firefox?

Question

I have had prompts pop-up from the bottom of the browser, most recently one that gave me the option to "Choose What I Share". Is there any way to prevent these from popping up? I was in the middle of typing a post to a forum when a pop-up prompt showed up. Due to the something with the site I was on, the whole page reloaded because the window size changed, and everything I had typed up to that point was erased with the reload.
Is there a way to prevent these prompts from popping up? If so, where do I look in order to adjust whatever needs adjusting?

Answer 1

The pop-ups I am referring to are not like the pop-up windows that show up depending on which sites I go to. I am referring to the small bar that appears at the bottom of the browser window, usually asking if I want to do something to modify my Firefox experience. As mentioned before, the most recent one was the one that asks me to "Choose What I Share". This affected the screen display, not unlike the way the screen is affected when the option to find text on the page pushes the entire page up.