Bing is not a browser. It is a website/search engine.

Are you talking about the home page? https://support.mozilla.org/en-US/kb/how-to-set-the-home-page

Or the search engine? Type about:preferences#search<enter> in the address box. You can select any search engine to be your default from here.

You can also remove any engine from here.

New Tab Settings https://addons.mozilla.org/firefox/addon/new-tab-override/

https://support.mozilla.org/en-US/kb/customize-new-tab-page

https://support.mozilla.org/en-US/kb/hide-or-display-content-new-tab

Did you check the target line in the Properties of this shortcut ?

Hi Erwin, that's a great photo. However, I'm not sure what the problem is with your Firefox. If you hover your mouse pointer over the Firefox button on the Windows Task bar (the button with the blue underline), does Windows show a little thumbnail image of at least one open page? If you try to click that image, does the page then appear on the screen? Or is that the problem -- the page does not appear on the screen -- it seems to be off the screen.