Magnify means to zoom in or out on a page. The IE uses a magnifying glass to identify it in the lower righthand corner. It is normally set for 100%. For vision aid, I set mine to 125%, but it is set that way when I get the page displayed. If I change the setting to 150% or down to 75%. I sometimes encounter rearranged link positions (more so in going small to large)
Computers use a thing called wordwrap. When you come to the end of a line, it auto carriage returns and types on the next lower line. If you reposition the end of that line by changing the size of the viewed page, things like links can get misplaced.
There used to be a related problem from the cache realm. Sometimes a new page was displayed against the format/positions of an old page and links were no longer where they were intended to be. But I think the coding gurus have solved that problem. A refresh never hurt though.
So, in simpler terms, if you've unknowingly changed your display size, your link positions could be in unexpected places. Assure 100% magnification and refresh. If Mozilla doesn't have a magnifying glass icon in the window surround area. surely there will be a command listed under your browser command line - tools or view - to change the zoom level.
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Tim Davis 'Your Saving Grace' Steve Miller Band (1969)
"...Yesterday's at least a mile back."
Dale Peters 'Dreaming in the Country' James Gang (1971)