Regardless of screen or Internet location this problem is extremely annoying. Many times I am trying to change the words in a search input field. Clicking on the left button to highlight or highlight drag a number of words fails but a menu which looks similar to the add-in menu for Tab Mix Plus appears. Tab mix plus has no entry for turning on a left click menu or turning off a left click menu. Nor does Firefox. How can I get this menu to stop appearing. Continuing to left click final works after the menu has appeared several time. Some times it does not do it at all.