Hi ayuratih, after installation of Firefox or an update -- there have been two this week -- you usually get a "first run" page. However, it should not return until the next update.

Is there a way to prevent first run pages? I don't recall hearing of one, but perhaps another volunteer is familiar with one.

If the first run page somehow/accidentally got set as your home page, though, you can change that on the Preferences page. More info in this article: How to set the home page.

Some update pages you can hide by settings browser.startup.homepage_override.mstone = "ignore"