Occasionally, I get abnormal behaviour from the Firefox Desktop for XP. When this happens, for example, the mouse wheel magnifies and de-magnifies the page.
Also a left-click of the mouse will high-light text, if a dialogue box is selected, I can't enter text with the keyboard. When I click on the tab toolbar menu it immediately populates all entries under that particular tab.
Wšykne wótegrona (2)
I should add that after the last update, I left-clicked on the tab bar where it was unpopulated by tabs. This produced a new tab as if I had left-clicked on the plus sign at the end of the tabs population on the tab bar. It was after this event that every thing with hairy.
BTW, I use the dvorak keyboard, although that shouldn't be a factor.
Sounds that the Ctrl key somehow got stuck in pressed state or Firefox didn't detect that the key was no longer pressed.
You can set mousewheel.with*.action pref(s) like mousewheel.withcontrolkey.action to 0 to perform a scroll.
See: