this problem has not been solved.

First, maximize your current Firefox window, then minimize it and drag the Firefox window to the monitor you want it to open. Then close Firefox to save the setting. When you restart Firefox, it should appear on the correct monitor and then you can maximize again.

I want FF4 to always open on Monitor 1. If you click on a link that "opens in a new window", it opens on Monitor 2 and from then on all FF4 windows open on Monitor 2.

Firefox 3.6x did not have this problem.

The suggestion from silkphoenix works once, until you click on a link that opens a new window, then FF always opens on Monitor 2... the wrong monitor.

I don't and won't use tabs.

James

duplicate my post from a similar question

Try to download "actual multiple monitors" and create a rule for all firefox windows open on necesarry monitor. I'm using this configuration for many programs.. This prog is shareware but with 30-days trial.

I would like to see Mozilla address this by adding one or two preferences for those of us who use multiple monitors. Something like "Monitor Precedence" with a dropdown listing available monitors by number, as well as "Monitor Precedence for New Windows." So if I ctrl+N to get a new window, I can choose whether or not it opens on top of Firefox on the first monitor, or just opens the new window on the second monitor.

I like to keep everything in one window in tabs, but sometimes I need to cross-reference websites, so I'll drag the tabs I need to the second screen. The action of dragging a tab onto another monitor alone is enough to convince Firefox that it should open on the second monitor the next time it starts. It never works the other way around. Once I drag a single tab to the second screen it suddenly believes it should always reside there. Very annoying.

I've found forum posts complaining about this dating back to 2008. This problem has never been solved. It needs to be addressed.