How can I move/combine toolbars on the same line to gain more screen space ??
In IE you can lock or unlock toolbars and grag them and move to another line to gain more screen space & still have all you need up there.
How can I do this in Fire-fox ??
ప్రత్యుత్తరాలన్నీ (2)
You can only combine the content of several toolbars on one toolbar if the toolbars support that feature. If that is possible then you can do that via the View > Toolbars > Customize window or via the options of that toolbar (Tools > Add-ons > Extensions).
https://support.mozilla.com/en-US/kb/How+to+customize+the+toolbar
You don't move an entire toolbar all at once, it's done one button or element at a time. As cor-el mentioned, some addon toolbars don't "customize" too good.